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JSI Tip 0155 - Speed up file system activity.

If you have some extra RAM and an active file system, you can speed up file system activity by increasing the IoPageLockLimit from the default 512K bytes to 4096K bytes or more. Edit:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Memory Management

IoPageLockLimit type REG_DWORD Default: 512K

This entry is the maximum number of bytes that can be locked for I/O operations. When the value is 0, the system defaults to 512K. The largest value is based on the amount of memory in your system. You MUST limit this entry to:

Amount of physical memory          Maximum lock limit
   Less than 64 MB             Physical memory minus 7 MB 
   64 MB–500 MB                Physical memory minus 16 MB 
   512 MB and greater          Physical memory minus 64 MB

Before making changes, get a baseline by using performance monitor for a representative period of time. Make your changes in small increments and measure performance after each change.

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