The most voluminous program elements - shared libraries, which are standard for almost all virtual media, and besides, did not change during program execution. This allows you to use them immediately in all media, making reference to this physical domain. In Virtuozzo is implemented using the mmap, which is designed to work with memory cards. If the process has the right to change the common code, the kernel copies the first segment in the free area of memory, and only then change its contents.
A similar mechanism is used and the optimization of disk drives. To support SWsoft developers have implemented additional layer between the VFS - virtual file system, Unix, and drivers of physical file systems such as ext2, RaiserFS or others. This layer, called VZFS, provides storage does not modify files in a single copy. This layer also allows copying mechanism for recording and optimization of memory described above.
When using such a system optimization it is important to solve the problem of upgrading the software. This operation is logically done centrally, to upgrade the program also had to drive only one copy. To realize this possibility in the SWsoft has developed a specialized tool of centralized updating.
No comments:
Post a Comment