text:
|Publication number
|Publication type
|Application number
|Publication date
|Apr 18, 2006
|Filing date
|Dec 6, 2002
|Priority date
|Dec 6, 2002
|Fee status
|Also published as
|Publication number
|Alexander T. Garthwaite
|Original Assignee
|Sun Microsystems, Inc.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (77), Non-Patent Citations (59), Referenced by (33), Classifications (9), Legal Events (4)
|External Links: USPTO, USPTO Assignment, Espacenet
The present application is related to U.S. Patent Application Ser. No. 10/313,878 of Alexander T. Garthwaite for Detection of Dead Regions during Incremental Collection, which was filed on the same day as this application.
1. Field of the Invention
The present invention is directed to memory management. It particularly concerns what has come to be known as "garbage collection."
2. Background Information
In the field of computer systems, considerable effort has been expended on the task of allocating memory to data objects. For the purposes of this discussion, the term object refers to a data structure represented in a computer system's memory. Other terms sometimes used for the same concept are record and structure. An object may be identified by a reference, a relatively small amount of information that can be used to access the object. A reference can be represented as a "pointer" or a "machine address," which may require, for instance, only sixteen, thirty-two, or sixty-four bits of information, although there are other ways to represent a reference.
In some systems, which are usually known as "object oriented," objects may have associated methods, which are routines that can be invoked by reference to the object. They also may belong to a class, which is an organizational entity that may contain method code or other information shared by all objects belonging to that class. In the discussion that follows, though, the term object will not be limited to such structures; it will additionally include structures with which methods and classes are not associated.
The invention to be described below is applicable to systems that allocate memory to objects dynamically. Not all systems employ dynamic allocation. In some computer languages, source programs must be so written that all objects to which the program's variables refer are bound to storage locations at compile time. This storage-allocation approach, sometimes referred to as "static allocation," is the policy traditionally used by the Fortran programming language, for example.
Even for compilers that are thought of as allocating objects only statically, of course, there is often a certain level of abstraction to this binding of objects to storage locations. Consider the typical computer system 10 depicted in
Additionally, the actual physical operations performed to access some of the most-recently visited parts of the process's address space often will actually be performed in the cache 12 or in a cache on board microprocessor 11 rather than on the RAM 14, with which those caches swap data and instructions just as RAM 14 and system disk 17 do with each other.
A further level of abstraction results from the fact that an application will often be run as one of many processes operating concurrently with the support of an underlying operating system. As part of that system's memory management, the application's memory space may be moved among different actual physical locations many times in order to allow different processes to employ shared physical memory devices. That is, the location specified in the application's machine code may actually result in different physical locations at different times because the operating system adds different offsets to the machine-language-specified location.
Despite these expedients, the use of static memory allocation in writing certain long-lived applications makes it difficult to restrict storage requirements to the available memory space. Abiding by space limitations is easier when the platform provides for dynamic memory allocation, i.e., when memory space to be allocated to a given object is determined only at run time.
Dynamic allocation has a number of advantages, among which is that the run-time system is able to adapt allocation to run-time conditions. For example, the programmer can specify that space should be allocated for a given object only in response to a particular run-time condition. The C-language library function malloc( ) is often used for this purpose. Conversely, the programmer can specify conditions under which memory previously allocated to a given object can be reclaimed for reuse. The C-language library function free( ) results in such memory reclamation.
Because dynamic allocation provides for memory reuse, it facilitates generation of large or long-lived applications, which over the course of their lifetimes may employ objects whose total memory requirements would greatly exceed the available memory resources if they were bound to memory locations statically.
Particularly for long-lived applications, though, allocation and reclamation of dynamic memory must be performed carefully. If the application fails to reclaim unused memory—or, worse, loses track of the address of a dynamically allocated segment of memory—its memory requirements will grow over time to exceed the system's available memory. This kind of error is known as a "memory leak."
Another kind of error occurs when an application reclaims memory for reuse even though it still maintains a reference to that memory. If the reclaimed memory is reallocated for a different purpose, the application may inadvertently manipulate the same memory in multiple inconsistent ways. This kind of error is known as a "dangling reference," because an application should not retain a reference to a memory location once that location is reclaimed. Explicit dynamic-memory management by using interfaces like malloc( )/free( ) often leads to these problems.
A way of reducing the likelihood of such leaks and related errors is to provide memory-space reclamation in a more-automatic manner. Techniques used by systems that reclaim memory space automatically are commonly referred to as "garbage collection." Garbage collectors operate by reclaiming space that they no longer consider "reachable." Statically allocated objects represented by a program's global variables are normally considered reachable throughout a program's life. Such objects are not ordinarily stored in the garbage collector's managed memory space, but they may contain references to dynamically allocated objects that are, and such objects are considered reachable. Clearly, an object referred to in the processor's call stack is reachable, as is an object referred to by register contents. And an object referred to by any reachable object is also reachable.
The use of garbage collectors is advantageous because, whereas a programmer working on a particular sequence of code can perform his task creditably in most respects with only local knowledge of the application at any given time, memory allocation and reclamation require a global knowledge of the program. Specifically, a programmer dealing with a given sequence of code does tend to know whether some portion of memory is still in use for that sequence of code, but it is considerably more difficult for him to know what the rest of the application is doing with that memory. By tracing references from some conservative notion of a "root set," e.g., global variables, registers, and the call stack, automatic garbage collectors obtain global knowledge in a methodical way. By using a garbage collector, the programmer is relieved of the need to worry about the application's global state and can concentrate on local-state issues, which are more manageable. The result is applications that are more robust, having no dangling references and fewer memory leaks.
Garbage-collection mechanisms can be implemented by various parts and levels of a computing system. One approach is simply to provide them as part of a batch compiler's output. Consider FIG. 2's simple batch-compiler operation, for example. A computer system executes in accordance with compiler object code and therefore acts as a compiler 20. The compiler object code is typically stored on a medium such as FIG. 1's system disk 17 or some other machine-readable medium, and it is loaded into RAM 14 to configure the computer system to act as a compiler. In some cases, though, the compiler object code's persistent storage may instead be provided in a server system remote from the machine that performs the compiling. The electrical signals that carry the digital data by which the computer systems exchange that code are examples of the kinds of electromagnetic signals by which the computer instructions can be communicated. Others are radio waves, microwaves, and both visible and invisible light.
The input to the compiler is the application source code, and the end product of the compiler process is application object code. This object code defines an application 21, which typically operates on input such as mouse clicks, etc., to generate a display or some other type of output. This object code implements the relationship that the programmer intends to specify by his application source code. In one approach to garbage collection, the compiler 20, without the programmer's explicit direction, additionally generates code that automatically reclaims unreachable memory space.
Even in this simple case, though, there is a sense in which the application does not itself provide the entire garbage collector. Specifically, the application will typically call upon the underlying operating system's memory-allocation functions. And the operating system may in turn take advantage of various hardware that lends itself particularly to use in garbage collection. So even a very simple system may disperse the garbage-collection mechanism over a number of computer-system layers.
To get some sense of the variety of system components that can be used to implement garbage collection, consider FIG. 3's example of a more complex way in which various levels of source code can result in the machine instructions that a processor executes. In the
Most typically, the class files's byte-code routines are executed by a processor under control of a virtual-machine process 27. That process emulates a virtual machine from whose instruction set the byte codes are drawn. As is true of the compiler 23, the virtual-machine process 27 may be specified by code stored on a local disk or some other machine-readable medium from which it is read into FIG. 1's RAM 14 to configure the computer system to implement the garbage collector and otherwise act as a virtual machine. Again, though, that code's persistent storage may instead be provided by a server system remote from the processor that implements the virtual machine, in which case the code would be transmitted electrically or optically to the virtual-machine-implementing processor.
In some implementations, much of the virtual machine's action in executing these byte codes is most like what those skilled in the art refer to as "interpreting," so
Now, some of the functionality that source-language constructs specify can be quite complicated, requiring many machine-language instructions for their implementation. One quite-common example is a source-language instruction that calls for 64-bit arithmetic on a 32-bit machine. More germane to the present invention is the operation of dynamically allocating space to a new object; the allocation of such objects must be mediated by the garbage collector.
In such situations, the compiler may produce "inline" code to accomplish these operations. That is, all object-code instructions for carrying out a given source-code-prescribed operation will be repeated each time the source code calls for the operation. But inlining runs the risk that "code bloat" will result if the operation is invoked at many source-code locations.
The natural way of avoiding this result is instead to provide the operation's implementation as a procedure, i.e., a single code sequence that can be called from any location in the program. In the case of compilers, a collection of procedures for implementing many types of source-code-specified operations is called a runtime system for the language. The execution engines and the runtime system of a virtual machine are designed together so that the engines "know" what runtime-system procedures are available in the virtual machine (and on the target system if that system provides facilities that are directly usable by an executing virtual-machine program.) So, for example, the just-in-time compiler 29 may generate native code that includes calls to memory-allocation procedures provided by the virtual machine's runtime system. These allocation routines may in turn invoke garbage-collection routines of the runtime system when there is not enough memory available to satisfy an allocation. To represent this fact,
Although the
The arrangement of
The invention to be described below is applicable independently of whether a batch compiler, a just-in-time compiler, an interpreter, or some hybrid is employed to process source code. In the remainder of this application, therefore, we will use the term compiler to refer to any such mechanism, even if it is what would more typically be called an interpreter.
In short, garbage collectors can be implemented in a wide range of combinations of hardware and/or software. As is true of most of the garbage-collection techniques described in the literature, the invention to be described below is applicable to most such systems.
By implementing garbage collection, a computer system can greatly reduce the occurrence of memory leaks and other software deficiencies in which human programming frequently results. But it can also have significant adverse performance effects if it is not implemented carefully. To distinguish the part of the program that does "useful" work from that which does the garbage collection, the term mutator is sometimes used in discussions of these effects; from the collector's point of view, what the mutator does is mutate active data structures' connectivity.
Some garbage-collection approaches rely heavily on interleaving garbage-collection steps among mutator steps. In one type of garbage-collection approach, for instance, the mutator operation of writing a reference is followed immediately by garbage-collector steps used to maintain a reference count in that object's header, and code for subsequent new-object storage includes steps for finding space occupied by objects whose reference count has fallen to zero. Obviously, such an approach can slow mutator operation significantly.
Other approaches therefore interleave very few garbage-collector-related instructions into the main mutator process but instead interrupt it from time to time to perform garbage-collection cycles, in which the garbage collector finds unreachable objects and reclaims their memory space for reuse. Such an approach will be assumed in discussing FIG. 4's depiction of a simple garbage-collection operation. Within the memory space allocated to a given application is a part 40 managed by automatic garbage collection. In the following discussion, this will be referred to as the "heap," although in other contexts that term refers to all dynamically allocated memory. During the course of the application's execution, space is allocated for various objects 42, 44, 46, 48, and 50. Typically, the mutator allocates space within the heap by invoking the garbage collector, which at some level manages access to the heap. Basically, the mutator asks the garbage collector for a pointer to a heap region where it can safely place the object's data. The garbage collector keeps track of the fact that the thus-allocated region is occupied. It will refrain from allocating that region in response to any other request until it determines that the mutator no longer needs the region allocated to that object.
Garbage collectors vary as to which objects they consider reachable and unreachable. For the present discussion, though, an object will be considered "reachable" if it is referred to, as object 42 is, by a reference in the root set 52. The root set consists of reference values stored in the mutator's threads' call stacks, the CPU registers, and global variables outside the garbage-collected heap. An object is also reachable if it is referred to, as object 46 is, by another reachable object (in this case, object 42). Objects that are not reachable can no longer affect the program, so it is safe to re-allocate the memory spaces that they occupy.
A typical approach to garbage collection is therefore to identify all reachable objects and reclaim any previously allocated memory that the reachable objects do not occupy. A typical garbage collector may identify reachable objects by tracing references from the root set 52. For the sake of simplicity,
To avoid excessive heap fragmentation, some garbage collectors additionally relocate reachable objects.
Although this relocation requires the extra steps of copying the reachable objects and updating references to them, it tends to be quite efficient, since most new objects quickly become unreachable, so most of the current semi-space is actually garbage. That is, only a relatively few, reachable objects need to be relocated, after which the entire semi-space contains only garbage and can be pronounced free for reallocation.
Now, a collection cycle can involve following all reference chains from the basic root set—i.e., from inherently reachable locations such as the call stacks, class statics and other global variables, and registers—and reclaiming all space occupied by objects not encountered in the process. And the simplest way of performing such a cycle is to interrupt the mutator to provide a collector interval in which the entire cycle is performed before the mutator resumes. For certain types of applications, this approach to collection-cycle scheduling is acceptable and, in fact, highly efficient.
For many interactive and real-time applications, though, this approach is not acceptable. The delay in mutator operation that the collection cycle's execution causes can be annoying to a user and can prevent a real-time application from responding to its environment with the required speed. In some applications, choosing collection times opportunistically can reduce this effect. Collection intervals can be inserted when an interactive mutator reaches a point at which it awaits user input, for instance.
So it may often be true that the garbage-collection operation's effect on performance can depend less on the total collection time than on when collections actually occur. But another factor that often is even more determinative is the duration of any single collection interval, i.e., how long the mutator must remain quiescent at any one time. In an interactive system, for instance, a user may never notice hundred-millisecond interruptions for garbage collection, whereas most users would find interruptions lasting for two seconds to be annoying.
The cycle may therefore be divided up among a plurality of collector intervals. When a collection cycle is divided up among a plurality of collection intervals, it is only after a number of intervals that the collector will have followed all reference chains and be able to identify as garbage any objects not thereby reached. This approach is more complex than completing the cycle in a single collection interval; the mutator will usually modify references between collection intervals, so the collector must repeatedly update its view of the reference graph in the midst of the collection cycle. To make such updates practical, the mutator must communicate with the collector to let it know what reference changes are made between intervals.
An even more complex approach, which some systems use to eliminate discrete pauses or maximize resource-use efficiency, is to execute the mutator and collector in concurrent execution threads. Most systems that use this approach use it for most but not all of the collection cycle; the mutator is usually interrupted for a short collector interval, in which a part of the collector cycle takes place without mutation.
Independent of whether the collection cycle is performed concurrently with mutator operation, is completed in a single interval, or extends over multiple intervals is the question of whether the cycle is complete, as has tacitly been assumed so far, or is instead "incremental." In incremental collection, a collection cycle constitutes only an increment of collection: the collector does not follow all reference chains from the basic root set completely. Instead, it concentrates on only a portion, or collection set, of the heap.
Specifically, it identifies every collection-set object referred to by a reference chain that extends into the collection set from outside of it, and it reclaims the collection-set space not occupied by such objects, possibly after evacuating them from the collection set.
By thus culling objects referenced by reference chains that do not necessarily originate in the basic root set, the collector can be thought of as expanding the root set to include as roots some locations that may not be reachable. Although incremental collection thereby leaves "floating garbage," it can result in relatively low pause times even if entire collection increments are completed during respective single collection intervals.
Most collectors that employ incremental collection operate in "generations," although this is not necessary in principle. Different portions, or generations, of the heap are subject to different collection policies. New objects are allocated in a "young" generation, and older objects are promoted from younger generations to older or more "mature" generations. Collecting the younger generations more frequently than the others yields greater efficiency because the younger generations tend to accumulate garbage faster; newly allocated objects tend to "die," while older objects tend to "survive."
But generational collection greatly increases what is effectively the root set for a given generation. Consider
One could perform this tracing by simply inspecting all references in all other generations at the beginning of every collection interval, and it turns out that this approach is actually feasible in some situations. But it takes too long in other situations, so workers in this field have employed a number of approaches to expediting reference tracing. One approach is to include so-called write barriers in the mutator process. A write barrier is code added to a write operation to record information from which the collector can determine where references were written or may have been since the last collection interval. A reference list can then be maintained by taking such a list as it existed at the end of the previous collection interval and updating it by inspecting only locations identified by the write barrier as possibly modified since the last collection interval.
One of the many write-barrier implementations commonly used by workers in this art employs what has been referred to as the "card table."
Of course, there are other write-barrier approaches, such as simply having the write barrier add to a list of addresses where references where written. Also, although there is no reason in principle to favor any particular number of generations, and although
Some collectors collect the entire young generation in every interval and may thereafter perform mature-generation collection in the same interval. It may therefore take relatively little time to scan all young-generation objects remaining after young generation collection to find references into the mature generation. Even when such collectors do use card tables, therefore, they often do not use them for finding young generation references that refer to mature-generation objects. On the other hand, laboriously scanning the entire mature generation for references to young-generation (or mature-generation) objects would ordinarily take too long, so the collector uses the card table to limit the amount of memory it searches for mature-generation references.
Now, although it typically takes very little time to collect the young generation, it may take more time than is acceptable within a single garbage-collection cycle to collect the entire mature generation. So some garbage collectors may collect the mature generation incrementally; that is, they may perform only a part of the mature generation's collection during any particular collection cycle. Incremental collection presents the problem that, since the generation's unreachable objects outside the "collection set" of objects processed during that cycle cannot be recognized as unreachable, collection-set objects to which they refer tend not to be, either.
To reduce the adverse effect this would otherwise have on collection efficiency, workers in this field have employed the "train algorithm," which
The discussion that follows will occasionally employ the nomenclature in the literature by using the term car instead of car section. But the literature seems to use that term to refer variously not only to memory sections themselves but also to data structures that the train algorithm employs to manage them when they contain objects, as well as to the more-abstract concept that the car section and managing data structure represent in discussions of the algorithm. So the following discussion will more frequently use the expression car section to emphasize the actual sections of memory space for whose management the car concept is employed.
According to the train algorithm, the car sections are grouped into "trains," which are ordered, conventionally according to age. For example,
Conventionally, the car collected in an increment is the one added earliest to the oldest train, which in this case is car 75. All of the generation's cars can thus be thought of as waiting for collection in a single long line, in which cars are ordered in accordance with the order of the trains to which they belong and, within trains, in accordance with the order in which they were added to those trains.
As is usual, the way in which reachable objects are identified is to determine whether there are references to them in the root set or in any other object already determined to be reachable. In accordance with the train algorithm, the collector additionally performs a test to determine whether there are any references at all from outside the oldest train to objects within it. If there are not, then all cars within the train can be reclaimed, even though not all of those cars are in the collection set. And the train algorithm so operates that inter-car references tend to be grouped into trains, as will now be explained.
To identify references into the car from outside of it, train-algorithm implementations typically employ "remembered sets." As card tables are, remembered sets are used to keep track of references. Whereas a card-table entry contains information about references that the associated card contains, though, a remembered set associated with a given region contains information about references into that region from locations outside of it. In the case of the train algorithm, remembered sets are associated with car sections. Each remembered set, such as car 75's remembered set 90, lists locations in the generation that contain references into the associated car section.
The remembered sets for all of a generation's cars are typically updated at the start of each collection cycle. To illustrate how such updating and other collection operations may be carried out,
Block 102 represents a period of the mutator's operation. As was explained above, the mutator makes a card-table entry to identify any card that it has "dirtied" by adding or modifying a reference that the card contains. At some point, the mutator will be interrupted for collector operation. Different implementations employ different events to trigger such an interruption, but we will assume for the sake of concreteness that the system's dynamic-allocation routine causes such interruptions when no room is left in the young generation for any further allocation. A dashed line 103 represents the transition from mutator operation and collector operation.
In the system assumed for the
When the collector's interval first starts, it first processes the card table, in an operation that block 104 represents. As was mentioned above, the collector scans the "dirtied" cards for references into the young generation. If a reference is found, that fact is memorialized appropriately. If the reference refers to a young-generation object, for example, an expanded card table may be used for this purpose. For each card, such an expanded card table might include a multi-byte array used to summarize the card's reference contents. The summary may, for instance, be a list of offsets that indicate the exact locations within the card of references to young-generation objects, or it may be a list of fine-granularity "sub-cards" within which references to young-generation objects may be found. If the reference refers to an old-generation object, the collector often adds an entry to the remembered set associated with the car containing that old-generation object. The entry identifies the reference's location, or at least a small region in which the reference can be found. For reasons that will become apparent, though, the collector will typically not bother to place in the remembered set the locations of references from objects in car sections farther forward in the collection queue than the referred-to object, i.e., from objects in older trains or in cars added earlier to the same train.
The collector then collects the young generation, as block 105 indicates. (Actually, young-generation collection may be interleaved with the dirty-region scanning, but the drawing illustrates it for purpose of explanation as being separate.) If a young-generation object is referred to by a reference that card-table scanning has revealed, that object is considered to be potentially reachable, as is any young-generation object referred to by a reference in the root set or in another reachable young-generation object. The space occupied by any young-generation object thus considered reachable is withheld from reclamation. For example, it may be evacuated to a young-generation semi-space that will be used for allocation during the next mutator interval. It may instead be promoted into the older generation, where it is placed into a car containing a reference to it or into a car in the last train. Or some other technique may be used to keep the memory space it occupies off the system's free list. The collector then reclaims any young generation space occupied by any other objects, i.e., by any young-generation objects not identified as transitively reachable through references located outside the young generation.
The collector then performs the train algorithm's central test, referred to above, of determining whether there are any references into the oldest train from outside of it. As was mentioned above, the actual process of determining, for each object, whether it can be identified as unreachable is performed for only a single car section in any cycle. In the absence of features such as those provided by the train algorithm, this would present a problem, because garbage structures may be larger than a car section. Objects in such structures would therefore (erroneously) appear reachable, since they are referred to from outside the car section under consideration. But the train algorithm additionally keeps track of whether there are any references into a given car from outside the train to which it belongs, and trains's sizes are not limited. As will be apparent presently, objects not found to be unreachable are relocated in such a way that garbage structures tend to be gathered into respective trains into which, eventually, no references from outside the train point. If no references from outside the train point to any objects inside the train, the train can be recognized as containing only garbage. This is the test that block 106 represents. All cars in a train thus identified as containing only garbage can be reclaimed.
The question of whether old-generation references point into the train from outside of it is (conservatively) answered in the course of updating remembered sets; in the course of updating a car's remembered set, it is a simple matter to flag the car as being referred to from outside the train. The step-106 test additionally involves determining whether any references from outside the old generation point into the oldest train. Various approaches to making this determination have been suggested, including the conceptually simple approach of merely following all reference chains from the root set until those chains (1) terminate, (2) reach an old-generation object outside the oldest train, or (3) reach an object in the oldest train. In the two-generation example, most of this work can be done readily by identifying references into the collection set from live young-generation objects during the young-generation collection. If one or more such chains reach the oldest train, that train includes reachable objects. It may also include reachable objects if the remembered-set-update operation has found one or more references into the oldest train from outside of it. Otherwise, that train contains only garbage, and the collector reclaims all of its car sections for reuse, as block 107 indicates. The collector may then return control to the mutator, which resumes execution, as FIG. 8B's block 108 indicates.
If the train contains reachable objects, on the other hand, the collector turns to evacuating potentially reachable objects from the collection set. The first operation, which block 110 represents, is to remove from the collection set any object that is reachable from the root set by way of a reference chain that does not pass through the part of the old generation that is outside of the collection set. In the illustrated arrangement, in which there are only two generations, and the young generation has previously been completely collected during the same interval, this means evacuating from a collection set any object that (1) is directly referred to by a reference in the root set, (2) is directly referred to by a reference in the young generation (in which no remaining objects have been found unreachable), or (3) is referred to by any reference in an object thereby evacuated. All of the objects thus evacuated are placed in cars in the youngest train, which was newly created during the collection cycle. Certain of the mechanics involved in the evacuation process are described in more detail in connection with similar evacuation performed, as blocks 112 and 114 indicate, in response to remembered-set entries.
For each one of the evacuated object's references, the collector checks to see whether the location that it refers to is in the collection set. As blocks 134 and 136 indicate, the reference processing continues until all references in the evacuated object have been processed. In the meantime, if a reference refers to a collection-set location that contains an object not yet evacuated, the collector evacuates the referred-to object to the train to which the evacuated object containing the reference was evacuated, as blocks 138 and 140 indicate.
If the reference refers to a location in the collection set from which the object has already been evacuated, then the collector uses the forwarding pointer left in that location to update the reference, as block 142 indicates. Before the processing of
Now, some train-algorithm implementations postpone processing of the references contained in evacuated collection-set objects until after all directly reachable collection-set objects have been evacuated. In the implementation that
As FIG. 8's blocks 112 and 114 indicate, this processing of collection-set remembered sets is performed initially only for entries that do not refer to locations in the oldest train. Those that do are processed only after all others have been, as blocks 152 and 154 indicate.
When this process has been completed, the collection set's memory space can be reclaimed, as block 164 indicates, since no remaining object is referred to from outside the collection set: any remaining collection-set object is unreachable. The collector then relinquishes control to the mutator.
Processing always starts with the oldest train's earliest-added car, so the garbage collector refers to car 1.1's remembered set and finds that there is a reference from object L into the car being processed. It accordingly evacuates object A to the train that object L occupies. The object being evacuated is often placed in one of the selected train's existing cars, but we will assume for present purposes that there is not enough room. So the garbage collector evacuates object A into a new car section and updates appropriate data structures to identify it as the next car in the third train.
Since car 1.1 no longer contains live objects, it can be reclaimed, as
The next step is to process the next car, the one whose index is 1.2. Conventionally, this would not occur until some collection cycle after the one during which car 1.1 is collected. For the sake of simplicity we will assume that the mutator has not changed any references into the generation in the interim.
In the state that
The collector accordingly processes car 2.1 during the next collection cycle, and that car's remembered set indicates that there are two references outside the car that refer to objects within it. Those references are in object K, which is in the same train, and object A, which is not. Inspection of those references reveals that they refer to objects I and J, which are evacuated.
The result, depicted in
So car 3.1 is processed next. Its sole object, object L, is referred to inter-generationally as well as by a reference in the fourth train's object M. As
The next car to be processed is car 3.2, whose remembered set includes the addresses of references into it from objects B and L. Inspection of the reference from object B reveals that it refers to object A, which must therefore be evacuated to the fifth train before car 3.2 can be reclaimed. Also, we assume that object A cannot fit in car section 5.1, so a new car 5.2 is added to that train, as
A further observation needs to be made before we leave
In the state that
In that state, the next car to be processed has only inter-generational references into it. So, although its referred-to objects must therefore be evacuated from the train, they cannot be placed into trains that contain references to them. Conventionally, such objects are evacuated to a train at the end of the train sequence. In the illustrated implementation, a new train is formed for this purpose, so the result of car 4.2's processing is the state that
Processing continues in this same fashion. Of course, subsequent collection cycles will not in general proceed, as in the illustrated cycles, without any reference changes by the mutator and without any addition of further objects. But reflection reveals that the general approach just described still applies when such mutations occur.
The foregoing example shows that incremental collection—and train-algorithm collection in particular—provide a way to perform garbage collection effectively while reducing the incidence of excessively long pause times. But it can add significant overhead; identifying the locations of references to collection-set objects and evacuating collection-set objects thereby found to be potentially reachable can be expensive.
I have found that this overhead can be reduced significantly by performing these tasks's constituent operations in an order different from that described above.
The invention description below refers to the accompanying drawings, of which:
Although various aspects of the invention can be employed in incremental collectors that do not necessarily employ the train algorithm or operate in dedicated collection intervals, it will be exemplified below by such collectors.
Whereas it was assumed in the preceding discussion that each collection interval involved collection of only a single, oldest car in the generation, the example of
This variability in collection-set size will be a feature exhibited by most of the present invention's embodiments, although some may use a conventional, single-oldest-car approach. Among the embodiments that do employ some variability in collection-set size, the particular approach to arriving at the provisional collection set's membership is not critical. In most cases, though, that membership will be dictated to some degree by the need to limit pause times.
Block 206 represents the operation of scanning dirtied cards for references and, for each car section in the generation, memorializing in those cars's remembered sets the locations where references to their objects have been found. In this example, we will assume that the collector employs two generations, namely, a young generation and an old generation, and that the old generation is the sole train-algorithm-managed generation. In such a situation, the locations of references in the old generation to objects in the young generation would be memorialized at this time, too, but typically only by recording them against the young generation as a whole, not against individual sections within it.
In any event, the young generation is then collected, as block 208 indicates. The operation of identifying potentially reachable objects in the young generation begins, as was explained above, with an expanded root set. That is, the basic root set is supplemented by references in the old generation that refer to young-generation objects. To identify such references, the collector scans the references in the basic root set and additionally scans those locations in the old generation in which previous dirty-card-scanning operations have found references to young-generation objects. When the collector thereby finds references to young-generation objects, it considers those objects to be potentially reachable, and it follows potentially reachable objects' references to other objects, which it thereby also considers potentially reachable.
In this operation of scanning references, the collector will typically find not only references to young-generation objects but also some references to old-generation objects. When it does, the illustrated embodiment performs some old-generation-collection tasks in response and thereby avoids some scanning duplication that would otherwise occur during subsequent old-generation collection. Now, in the conventional train-algorithm routine described above in connection with
When the young-generation collection of block 208 has been completed, the collector has performed part of an operation that corresponds to the one described above in connection with FIG. 8A's block 110, which represents a conventional way of processing external references. In that operation, external references to collection-set objects were identified, the collection-set objects to which they referred were evacuated to the external-reference train, and any collection-set objects referred to from the external-reference train were evacuated to it, too. At the end of the young-generation collection represented by FIG. 13A's block 208, part of this has been done: the locations of the external references that refer to collection-set objects have been listed, although any resultant evacuation has been postponed.
The reason for postponing those evacuations is based on my observation that external references tend to be short-lived: they tend either to be call-stack references that quickly go out of scope or to be members of objects that quickly become unreachable. Since the external-reference train in the
The reason why block 208's young-generation collection includes marking non-collection-set cars that contain objects referred to by external references is to support an operation represented by block 210. Basically, that operation's purpose is to identify dead cars, i.e., cars that meet a criterion that can be satisfied only by a car that contains no reachable objects. The particular criterion used for this purpose is not critical, but example criteria are described in commonly assigned co-pending U.S. patent application Ser. No. 10/313,878 of Alexander T. Garthwaite for Detection of Dead Regions during Incremental Collection, which was filed on the same day as this application and is hereby incorporated by reference.
In the example dead-car-identification approaches described in those applications, remembered-set updating additionally includes updating oldest-car and/or youngest-car indicators for each car. If an entry being made into a given car's remembered set is located in a car older than the one represented by the given car's oldest-car indicator, that oldest-car indicator is updated to identify the car containing the reference for which the new remembered-set entry is being made. So the collector can rely on the fact that no reference located in a car younger than the one identified by the given car's oldest-car indicator refers to any object in the given car. The collector may similarly maintain youngest-car indicators.
In one way of identifying dead cars, any car marked as directly referred to by an external reference is considered potentially alive. And a given car is also marked as potentially alive if its oldest-car indicator is at least as old as some other car that has been marked as potentially alive. By such marking operations or similar ones, the collector can identify all potentially live cars and conclude that any remaining cars are dead. Cars thus identified as dead can be collected inexpensively; their remembered-set entries do not need to be processed, and no objects need to be evacuated from them. So the collector may supplement the provisional collection set by adding a dead car or cars to it to make up the final collection set. Block 210 represents such dead-car identification and collection-set supplementing.
As was mentioned above in connection with the conventional train-algorithm approach described above by reference to
Specifically, the collector builds scratch-pad lists for respective trains by placing in each list entries that tell where references to collection-set objects can be found in the respective train. Again, these lists will identify only locations that contain references to collection-set objects that are not in the collection set's dead cars; they will not contain entries for locations that contain only references to dead-car objects. With the scratch-pad lists thus built, they are accessed in reverse train order to find collection-set objects that should be evacuated to respective trains. The reason for thus processing the references in reverse train order is to reduce the number of subsequent evacuations. If a collection-set object is referred to from, say, both the seventh train and the twentieth train, it is better to evacuate it to the twentieth train rather than to the seventh train, because doing so avoids an evacuation that otherwise would likely be required when the seventh train comes up for collection.
Block 212 represents building those scratch-pad lists, and block 214 represents evacuating the collection-set objects referred to by references whose locations those lists identify. But the evacuation that block 214 represents includes only the evacuations performed in response to entries in the scratch-pad lists built from entries in the collection set's remembered set or sets; it does not include evacuations performed in response to the scratch-pad list corresponding to the external-reference train. Moreover, it does not include evacuations to the oldest train.
To understand the reason for these exceptions, recall that one policy implemented by the
As block 220 and 222 indicate, the collection set is then reclaimed and mutator execution resumes.
Note that performing the reference-locating operations both for internal and for external references before objects are evacuated in response to either operation enables the illustrated collector to do a couple of things that reduce collection cost. By locating the internal references before evacuation is performed in response to the located external references, the collector can evacuate some externally referred-to objects in response to internal references and thereby reduce the amount of floating garbage. At the same time, locating external references before evacuation is performed in response internal references enables the collector to identify dead cars and thereby reduce the amount of remembered-set processing and collection-set-object evacuation.
Mixing internal- and external-reference processing can yield advantages in other embodiments, too.
To understand the
But some train-algorithm embodiments may advance more-recently created trains ahead of some earlier-created trains, so an "older" train may sometimes be chronologically younger. This advancing of trains ahead of their chronological ages is what the
The purpose for thus making external-reference trains older is to respond to the fact that external references tend to be short-lived and that the external-reference train's contents are therefore likely soon to become mostly garbage and thus ripe for collection. But not all externally reachable objects will soon be garbage, and factors such as the age of the reference or the referred-to object give some indication of the referred-to object's tendency to become garbage soon; older objects tend to remain reachable longer and therefore should be put in younger trains. The
So, while block 234 represents an operation similar to the one described in connection with FIG. 13's block 208, the embodiment that
Block 240 represents thereafter evacuating collection-set objects in response to the entries in the scratch-pad lists, including the lists that are associated with the external-reference trains. The lists associated with those trains are processed in their order among the lists associated with other trains, and none of the external-reference trains has been accorded a seniority greater than the oldest train's. So processing the list in reverse train order will naturally comply with the requirement that the oldest train's list be processed last and that the only objects evacuated to the oldest train will be those referred to by references in no other trains.
As blocks 242 and 244 indicate, the collection set is then reclaimed and mutator execution resumes.
Although most train-algorithm implementations employ two generations, not all do.
By combining the processing of internal and external references, collectors that practice the present invention's teachings can reduce garbage-collection expense. The present invention therefore constitutes a significant advance in the art.
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|Pattern matching process scheduler in message passing environment
|May 1, 2012
|May 13, 2014
|Concurix Corporation
|Recompiling with generic to specific replacement
|Jul 17, 2012
|Jul 29, 2014
|Concurix Corporation
|Pattern extraction from executable code in message passing environments
|Aug 30, 2013
|Nov 11, 2014
|Pure Storage, Inc.
|Garbage collection in a storage system
|Aug 10, 2012
|May 26, 2015
|Concurix Corporation
|Experiment manager for manycore systems
|Jun 19, 2012
|Jun 2, 2015
|Concurix Corporation
|Usage aware NUMA process scheduling
|Nov 10, 2014
|Feb 2, 2016
|Pure Storage, Inc.
|Garbage collection in a storage system
|May 1, 2012
|Aug 16, 2016
|Microsoft Technology Licensing, Llc
|Many-core process scheduling to maximize cache usage
|Jul 17, 2012
|Feb 21, 2017
|Microsoft Technology Licensing, Llc
|Pattern matching process scheduler with upstream optimization
|Mar 29, 2013
|May 30, 2017
|Microsoft Technology Licensing, Llc
|Relationships derived from trace data
|Mar 8, 2002
|Jan 22, 2004
|Timothy Renouf
|Loading object-oriented computer programs
|Feb 24, 2003
|Aug 26, 2004
|Garthwaite Alexander T.
|Staging the processing of remembered-set entries as part of collection based on the train algorithm
|Oct 5, 2007
|Apr 9, 2009
|Microsoft Corporation
|Nondeferred reference-counting garbage collection using overlooking roots
|Oct 5, 2007
|Apr 9, 2009
|Microsoft Corporation
|Applications of overlooking root information for improving nondeferred reference-counting garbage collection
|Sep 22, 2008
|Apr 1, 2010
|Jiva Azeem S
|Gpu assisted garbage collection
|Jul 1, 2009
|Jan 6, 2011
|Frost Gary R
|Combining classes referenced by immutable classes into a single synthetic class
|Mar 2, 2010
|Sep 8, 2011
|Caspole Eric R
|Gpu support for garbage collection
|U.S. Classification
|International Classification
|Cooperative Classification
|European Classification
|Dec 6, 2002
Owner name: SUN MICROSYSTEMS, INC., CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:GARTHWAITE, ALEXANDER T.;REEL/FRAME:013556/0536
Effective date: 20021205
|Sep 16, 2009
|Fee payment
Year of fee payment: 4
|Sep 18, 2013
|Fee payment
Year of fee payment: 8
|Dec 14, 2015
Owner name: ORACLE AMERICA, INC., CALIFORNIA
Free format text: MERGER AND CHANGE OF NAME;ASSIGNORS:ORACLE USA, INC.;SUN MICROSYSTEMS, INC.;ORACLE AMERICA, INC.;REEL/FRAME:037280/0221
Effective date: 20100212


text:
Learn more about C. C. COOPER (LYE) LIMITED. Check the company's details for free and view the Companies House information, company documents and list of directors.
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|Tangible Fixed Assets
|£ 2,562,429
|Current Assets
|£ 244,467
|Tangible Fixed Assets Depreciation
|£ 686,483
|Provisions For Liabilities Charges
|£ 4,070
|£ 44,654
|Shareholder Funds
|£ 1,858,074
|Profit Loss Account Reserve
|£ 1,121,575
|Revaluation Reserve
|£ 236,499
|Called Up Share Capital
|£ 500,000
|Net Assets Liabilities Including Pension Asset Liability
|£ 1,858,074
|Total Assets Less Current Liabilities
|£ 2,137,294
|Net Current Assets Liabilities
|£ 425,135
|Creditors Due Within One Year
|£ 669,602
|Cash Bank In Hand
|£ 128,180
|Stocks Inventory
|£ 71,633
|Share Capital Allotted Called Up Paid
|£ 500,000
|Number Shares Allotted
|£ 500,000
|Tangible Fixed Assets Disposals
|£ 10,247
|Tangible Fixed Assets Additions
|£ 83,372
|Tangible Fixed Assets Cost Or Valuation
|£ 3,222,045
|Tangible Fixed Assets Depreciation Charged In Period
|£ 107,415
|Tangible Fixed Assets Depreciation Decrease Increase On Disposals
|£ 7,423
|Creditors Due After One Year
|£ 275,150
Information about the Private Limited Company C. C. COOPER (LYE) LIMITED has been prepared for information purposes only. It is not intended to be nor does it constitute legal advice. This is public information provided by the official company register.

subset: commoncrawl


text:
Personal Values as A Catalyst for Corporate Social Entrepreneurship
- 3.3k Downloads
The literature acknowledges a distinction between immoral, amoral and moral management. This paper makes a case for the employee (at any level) as a moral agent, even though the paper begins by highlighting a body of evidence which suggests that individual moral agency is sacrificed at work and is compromised in deference to other pressures. This leads to a discussion about the notion of discretion and an examination of a separate, contrary body of literature which indicates that some individuals in corporations may use their discretion to behave in a socially entrepreneurial manner. My underlying assumption is that CSR isn't solely driven by economics and that it may also be championed as a result of a personal morality, inspired by employees' own socially oriented personal values. A conceptual framework is put forward and it is suggested that individuals may be categorized as Active or Frustrated Corporate Social Entrepreneurs; Conformists or Apathetics, distinguished by their individualistic or collectivist personal values. In a discussion of the nature of values, this paper highlights how values may act as drivers of our behavior and pays particular attention to the values of the entrepreneur, thereby linking the existing debate on moral agency with the field of corporate social responsibility.
Key wordsChampions discretion entrepreneurship corporate social entrepreneur (CSE) corporate social responsibility (CSR) moral agency personal values policy entrepreneurship social entrepreneurship social responsibility
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text:
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The hotel offers its guests a total of 152 standard rooms off history, very comfortable and decorated in English style, with the classicism of a legendary hotel in the city. Of the 152 rooms of which 7 are singles.
Services and facilities available:
Included in the service of the Presidential Suite, you will receive a welcome cocktail in the Lounge Bar Room Service Access Business Center 3rd floor.
Services and facilities available:


text:
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- Protected by our 12 MONTH WARRANTY


text:
Edmiston signs superyacht Jess Sea for sale
by Malcolm MacLean
Bill Sanderson at Edmiston & Company in Palm Beach sends in details of his latest listing, the 26.5m sailing yacht Jess Sea.
Built by Merrifield-Roberts in 2002, she accommodates seven guests in three staterooms: a full beam master suite aft plus two twin cabins and a Pullman berth. A special feature is her large full width saloon flooded with natural light due to large hull ports. Bill says Jess Sea has left Cabo San Luca and is located in New England for the summer. Her asking price is $2.95 million.
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Very Easy Vogue 9099; ca. 1975; Misses' Top and Skirt. Loose fitting top has jewel neckline, applied neckband and V shaped inset, seven eights length raglan sleeves, elasticized waistline with attached self bow, back zipper closing and topstitch trim. Below knee length, fit and flared skirt has waistband and back zipper closing.
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[insert your photos of this pattern made up]
Wishlist Edit
[insert your username, and make sure your preferences allow for people to contact you via e-mail. Do not list your email address here!]


text:
The stomach is found in the upper abdomen and forms part of the digestive system, connecting the esophagus to the small intestine. It digests food and nutrients. Stomach Diseases include non-cancerous disorders and gastric malignancies.
Non-cancerous conditions we treat include peptic ulcers, acid hypersecretory conditions such as Zollinger-Ellison syndrome, and gastrointestinal bleeding. Stomach cancer, also called gastric cancer or malignancies, may include cancer of the upper part of the stomach where it meets the esophagus, and is called gastric cardia cancer. Stomach cancer that occurs in the lower stomach is called non-cardia gastric cancer.
As a major academic medical center, NewYork-Presbyterian is home to the most up-to-date diagnostic tools, research and prevention programs, therapeutic treatments and best patient care available to treat Stomach Diseases. These include a range of minimally invasive surgical and diagnostic procedures, as well as innovative medical interventions.
You might also enjoy visiting our Health Library and Interactive Media Library for information on Digestive Diseases.


text: I've been a reading machine lately. A few of the books I'm so far behind about talking about (bad blogger) and the rest have all been read fairly recently. Like as in I finished another book 20 minutes ago. ;) If you like to read, then this is your post to find out what I've been reading and what I recommend. :) #1: The Paris Wife by Paula McLain Goodreads.com Synopsis: A deeply evocative story of ambition and betrayal, The Paris Wife captures a remarkable period of time and a love affair ... View the Post


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"It's time, old captain, lift anchor, sink! The land rots; we shall sail into the night; if now the sky and sea are black as ink our hearts, as you must know, are filled with light.
Only when we drink poison are we well — we want, this fire so burns our brain tissue, to drown in the abyss — heaven or hell, who cares? Through the unknown, we'll find the new." - Charles Baudelaire
FR // 13.05.2016 // 23:00 // 7,00€ // No Lineup // Goethebunker, Goethestraße 67, 45130 Essen


text:
Why did I choose Germany?
I choose Germany because i find their culture and history so interesting, it is a beautiful country and have a lot of things to discover.
Common sports include winter sports, boxing, volleyball, basketball, ice hockey, tennis,. Water sports like underwater diving are popular in Germany as well, but the most popular sport is football.
General information
Its official name is the Federal Republic of Germany , in german Bundesrepublik Deutschland.
The country consists of 16 states and its capital and largest city is Berlin
covers an area of 357,021 square kilometers
Its a member of the European Union and is the most populous member state with 80.6 million inhabitants
the actual president is Joachim Gauck
the prime minister is Angela Merkel
Is located in western - central Europe
Christianity is the official religion
the official language is german
Germany is the major economic and political power of the European continent, and the official currency is the euro
Germany is a rich and powerful country an Colombia stills development
Germany is one of the most influential countries in the word, wile Colombia not
Germany has developed significant achievements in science, medicine, technology and infrastructure, while Colombia is limited to the share of agriculture (coffee, bananas and flowers)
Germany has a very significant global war history, while Colombia has national conflicts
The education and security of Germany is better than Colombian`s
Colombia is bigger than Germany
Yes, I would live in Germany, because I identify with their culture and is a highly developed country with many opportunities to work and study, plus a high quality of life and excellent security.
Both are democratic republics
Football is the most popular sport
both have important rivers
They are touristic counties
Its origins are unknown, it is speculated that they were inspired by the colors of the uniforms of the Free Corps (Corps release) against the Napoleonic army, or, taken from the flag of the Holy Roman Empire, which also contain these colors.
The coat of arms of Germany has its origin in different symbols belonging to the period of the Holy Roman Empire.
Mercedes-Benz, BMW, SAP, Siemens, Volkswagen, Adidas, Audi, Allianz, Porsche, Bayer, Bosch, and Nivea.
Oktoberfest is the world's largest fair held annually in Munich, Bavaria, Germany. It is a 16-day festival running from late September to the first weekend in October with more than 6 million people from around the world attending the event every year. Only beer conforming to the Reinheitsgebot, at a minimum of approximately 6% alcohol by volume may be served at Oktoberfest. The beer must also be brewed within the city limits of Munich. Beers meeting these criteria may be designated Oktoberfest Beer.
Auschwitz-Birkenau museum
Cologne cathedral
Frankfurt train station
River Rin
Neuschwanstein castle
German parliament building Reichstag
Holocaust Memorial
Brandenburg Gate
Alianz arena
It is believed that the tradition of the Christmas tree originated in Germany in the seventeenth century. In Germany it is used to decorate the tree with real candles.
Germany has the best public transportation system in the world. Even so all Germans have their own car.
The Sleeping Beauty Castle from Disney is inspired by Neuschwanstein Castle in Bavaria.
The most important scientist of the twentieth century, Albert Einstein was born in Germany
Over 300 bunkers and hundreds of kilometers of underground tunnels built during the Nazi-era still remain under the modern city of Berlin
The German Hans Riegal invented the famous Gummy bears.
The Berlin Wall was a barrier constructed by the German Democratic Republic starting on 13 August 1961, that completely cut off (by land) West Berlin from surrounding East Germany and from East Berlin. The barrier included guard towers placed along large concrete walls,which circumscribed a wide area later known as the "death strip"
The European Central Bank (ECB) is the central bank for the euro and administers the monetary policy of the Eurozone. It is located in the city of Frankfurt
BY: Natalia Uribe Osorio
German selection has won three World Cups: Switzerland 1954 ,west Germany 1974 and Italy 1990
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text:
amy kuschel / Sample Learn More
Amy Kuschel 'Gretchen'
/ Resell It & Make Up To: $1,317.60 Learn More
Classic trumpet shape Italian silk mikado gown. Color: Candle, Size 8 street, size 10 tag. Will need to be cleaned.
The better the craftsmanship, the better the couture!
Gretchen is designed and crafted in San Francisco with particular attention to silhouette. Our figure flattering classic trumpet shape highlights the perfection of the female form from every angle.
Fabricated using gorgeous French Guipure lace mixed with Italian silk mikado, Gretchen is a richly textured architectural statement.
Our vintage inspired "Ferris Wheel" Guipure lace adorns the strapless bodice with layered grosgrain ribbon trimmings, silk cloth covered buttons, and French Guipure floral appliques cleverly placed to showcase your waistline and to highlight the vintage inspired train attachment.
Gretchen is ever so smart and just a tad preppy.
Note: This is a sample from a Nearly Newlywed 'preferred boutique partner.'
- Condition: sample
- Profesionally Cleaned: no
- Alterations: no
- US Street Size: 08
- Dress Tag Size: 10
- Bust: 36
- Waist: 28
- Hips: 38
- Tallest Wearable Height: 5' 9"
- Fabric: silk mikado
- Silhouette: trumpet
- Neckline: strapless
- Features: back detail
- Dress Length: full
Once you have placed your order the Seller will be notified to pack and ship the gown. The seller will then ship the item to us and our inspection and authentication team will check that it is authentic and matches to the seller's description. The item will then be shipped to you upon approval.
Dress Q & A
Have a question not answered here? Contact us below.
Try It On - No Risk Return Policy: Have your cake & eat it too. Returns accepted on all items. More details


text:
I ate cheese before I went to bed last night and I dreamnt that I was in a car with a girl and she gave me a b*owjob when we pulled over..
It seemed so real I genuinely thought I was gonna get laid... then I woke up.. Now I'm sad. 😂
- Don't be sad, Alex you'll get laid one day! ❤Vote A
- Breh, u iz gonna die a virgin fam.Vote B
- I LOVE CHEESE! 🐀Vote C
- DON'T LET YOUR DREAMS BE DREAMS!Vote D
Select a gender to cast your vote:
I'm a GirlI'm a Guy


text:
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Listen to free music played by DerekFordPhoto
Blip.fm is internet radio made social. It's easy to search for, play, and discover free music recommended by real people. Join today to create your own free station and start listening to @DerekFordPhoto.
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If an item you ordered from TextbookRush does not meet your expectations due to an error on our part, simply fill out a return request and then return it by mail within 30 days of ordering it for a full refund of item cost.
Learn more about our returns policy
Description: transcript is a disturbing document. Using the techniques of concrete and visual poetry, Heimrad Bäcker presents quotations from the Holocaust's planners, perpetrators, and victims. The book offers a startling collection of documents that confront us with details from the bureaucratic world of the Nazis and the intimate worlds they destroyed. Bäcker's sources range from victims' letters and medical charts to train schedules and the telephone records of Auschwitz. His transcriptions and reworkings of these sources serve as a reminder that everything about the Shoah was spoken about in great detail, from the most banal to the most monstrous. transcript shows us that the Holocaust was not "unspeakable,†but was an eminently describable and described act spoken about by thousands of people concerned with the precision and even the beauty of their language.
Limited time offer:
Get the first one free! (?)
All the information you need in one place! Each Study Brief is a summary of one specific subject; facts, figures, and explanations to help you learn faster.
List price: $16.95Copyright year: 2010Publisher: Dalkey Archive PressPublication date: 2/1/2010Binding: PaperbackPages: 153Size: 6.00" wide x 9.00" long x 0.50" tall Weight: 0.528Language: English
Heimrad B�cker (1925-2003) was a poet, a photographer, and the editor of the journal neue texte and the Austrian avant-garde press Edition Neue Texte. As a teenager, he was active in the regional leadership of the Hitler Youth and joined the Nazi party when he turned eighteen. After the war, he studied philosophy and wrote his doctoral dissertation on Karl Jaspers. Beginning in the late 1960s, B�cker attempted to come to terms with his wartime activity.
Patrick Greaney is assistant professor of German and comparative literature at the University of Colorado at Boulder.
Gert Jonke is counted among Austria's most important authors and dramatists. Among other prizes, he received the Ingeborg Bachmann Prize, the Erich Fried Prize, and the Grand Austrian State Prize for Literature. He died in 2009 at the age of 62.Vincent Kling is professor of German and comparative literature at La Salle University in Philadelphia.
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text:
AP Tourist Home
Call us 1800-300-2400-1 (Toll Free) and Get additional Discount upto 50% for this Hotel.
You are getting lowest possible rate for this hotel
- About Hotel
- Reviews
About AP Tourist Home
Located at Jew Street, AP Tourist Home is a low cost property in Cochin. It is a good option for cost conscious travelers, those who are visiting Cochin on tight budget. It features total 52 Non Ac rooms for accommodation. Front desk in hotel is operational 24 hours to assist guest. For the safety of guest it has security service. Guest can park their vehicle in the free parking space of the hotel premises. It provide clean and comfortable stay at an affordable price. The rooms in this hotel are neat, clean and well maintained. Each room is equipped with all required amenities. Cochin attract thousand of tourist for it;s beaches and forts.
Checkin Time: 0 pm
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One man of whom I have been critical about chose the grand stage to underline his importance and VVS Laxman did so most stylishly. He showed that in his fragile frame lies a tough mind. He played a highly pleasing innings and his wristy strokes were a delight.
Laxman has always been known for his timing and some of his wristy strokes indeed can take your breath away. His stylish century pushed India to its eventual score of 293 that proved far too much for Pakistan under lights. His innings was the kind of knock that I enjoyed thoroughly for it was a celebration of senses. Batting elevates itself to an art form when this elegant batsman is at the crease.
I thought Pakistan had done well enough when they asked India to take first strike and proceeded to produce a highly disciplined effort. There was no profusion of no balls and wides as had been the case in previous games. The bowlers, it appeared, had learnt their lessons and realised the difference of extras was the critical factor in the results of the game. They were thus not wayward on Wednesday and it immediately made an impact on Pakistan innings.
Shoaib Akhtar led the way with an impressive opening spell and largely contained a powerful Indian line-up. The rock-like solid Rahul Dravid and his prototype Mohammad Kaif were not allowed to get going.
Pakistan should not be faulting its bowlers though I must admit there were far too many runs in the final three overs that pushed India towards the 300-run mark.
In just a matter of two weeks, I have become a great admirer of Irfan Pathan. The youngster has attitude and oodles of confidence that is surprising for a cricketer as young as Irfan is. It was his spell that broke the back of Pakistan innings. It was an eminently chaseable total under lights but Irfan inflicted so enormous a damage on Pakistan innings that it never recovered despite the heroics of Moin Khan and Shoaib Malik.
I also cannot overlook L Balaji who has proved an ideal foil for Irfan Pathan as a new-ball partner. The delivery off which he dismissed Yasir Hameed was the best ball of the match. It pitched at the right spot and jagged back sharply to knock the off-stump out of the ground. Yasir was also guilty of appearing casual and late on his stroke. Pakistan never really recovered from the early blows.
Still you cannot take it away from Moin Khan and Shoaib Malik for fighting so valiantly and keeping Pakistan in the hunt till the end. They took a heavy toll of India's non-existent fifth bowler and going by the nature of matches in the series, there were many in the stands who were expecting a close finish.
They almost produced it but credit to India for keeping their cool. It was reflected in the cool catch which Balaji took off Malik at deep mid-wicket or when Yuvraj threw down the non-striker's stumps to catch Shoaib Akhtar short of his ground.
India were the deserving winners of the One-day series because they had better discipline than their hosts. One-day cricket is all about sticking to the basics and attending to those little details that make a huge difference in the end.
Pakistan relied on their bowlers to come good but indeed, it was their batsmen who produced a better effort than was imagined. Pakistan gave away too many extras in the first four matches and it had a critical bearing in the final outcome of the series.
The tour is far from over and Pakistan have enough time to make amends in the Test series that begins with the first game in Multan on Sunday. Their bowlers should reflect where they went wrong and it is critically important they find an answer to their no ball problems. They have a high-voltage pace attack and extra balls mean extra strain on a fast bowler's resources who actually should be fighting to retain every ounce of their energy.
The way it was in the One-day series, I feel the Test match clashes should be equally engrossing.