Search results
Results from the WOW.Com Content Network
Windows 95, Windows 98 and Windows Me use a similar file, and the settings for it are located under Control Panel → System → Performance tab → Virtual Memory. Windows automatically sets the size of the page file to start at 1.5× the size of physical memory, and expand up to 3× physical memory if necessary.
Some utilities prevented DLLs from allocating memory here, leaving more space for user programs. This was a standard technique also used by other memory optimization tools. [7] SoftRAM also claimed to increase the amount of virtual memory available by compressing the pages of virtual memory stored in the swap file on the hard disk, which has ...
By reducing the I/O activity caused by paging requests, virtual memory compression can produce overall performance improvements. The degree of performance improvement depends on a variety of factors, including the availability of any compression co-processors, spare bandwidth on the CPU, speed of the I/O channel, speed of the physical memory, and the compressibility of the physical memory ...
Virtual memory combines active RAM and inactive memory on DASD [a] to form a large range of contiguous addresses.. In computing, virtual memory, or virtual storage, [b] is a memory management technique that provides an "idealized abstraction of the storage resources that are actually available on a given machine" [3] which "creates the illusion to users of a very large (main) memory".
If present in memory and not privately modified the physical page is shared with file cache or buffer. Shared memory acquired through shm_open. The tmpfs in-memory filesystem; written to swap when paged out. The file cache including; written to the underlying block storage (possibly going through the buffer, see below) when paged out.
Thrashing is when the CPU performs 'productive' work less and 'swapping' work more. The overall memory access time may increase since the higher level memory is only as fast as the next lower level in the memory hierarchy. [2] The CPU is busy swapping pages so much that it cannot respond to users' programs and interrupts as much as required.
Bank switching is a technique used in computer design to increase the amount of usable memory beyond the amount directly addressable by the processor [1] instructions. It can be used to configure a system differently at different times; for example, a ROM required to start a system from diskette could be switched out when no longer needed.
The disadvantage of this approach is that memory swap files are slower to read from than 'actual' memory, which can lead to performance drops. [2] Another disadvantage is that, when running out of real memory, the system is relying on the applications to not use the additional memory despite it being allocated to them.