1. A system for executing instructions using a plurality of memory fragments for a processor, comprising: a global front end scheduler for receiving an incoming instruction sequence, wherein the global front end scheduler partitions the incoming instruction sequence into a plurality of code blocks of instructions; a plurality of virtual cores of the processor coupled to receive code blocks allocated by the global front end scheduler, wherein each virtual core comprises a respective subset of resources of a plurality of partitionable engines, wherein resources of each partitionable engine are operable to be partitioned to instantiate a virtual core with partitioned resources of other partitionable engines, wherein the code blocks are executed using the partitionable engines in accordance with a virtual core mode, and wherein each of the partitionable engines comprises a segment and a plurality of execution units; and a plurality of memory fragments coupled to the partitionable engines for providing data storage, wherein each of the plurality of memory fragments comprises an L1 cache, an L2 cache, a load store buffer and a store retirement buffer.