1. A system for providing hybrid kernel-space and user-space checkpointing of multi-process applications, the system comprising: one or more memory locations configured to store said applications executing on a host with a host operating system; one or more additional memory or storage locations configured to store checkpoints; one or more user-space interceptors preloaded into the address space of each application process, wherein said user-space interceptors comprise a barrier, creation of a per-process checkpointing thread, and an application virtualization space providing a private resource name space; and a kernel-space checkpointer implemented as a character device, wherein said kernel-space checkpointer is called while the execution of application processes are halted at said user-space barrier; wherein checkpointing is comprised of said application processes at said barrier being halted, the read function of said character device being called for each memory page in each process in said application on the checkpointing thread of said each application process, and said each page in said each application process' checkpoint being stored; wherein the read function of said character device skips memory pages not used by said application process; wherein the read function of said character device includes memory pages used by said application process; wherein said character device forwards the device pointer to the next page after every read.