Tuning memory resources

Viewing swap space usage

Information about the usage of the swap areas on your system can be seen using the swap -l command:

   path               dev  swaplo blocks   free
   /dev/swap          1,41      0 128000  88712
blocks shows the total size of a swap area in 512-byte disk blocks. free shows the number of blocks on the free list.

The number of unused 512-byte disk blocks in the swap area can be also be seen under the freeswp heading using sar -r (or mpsar -r for SMP):

   23:59:44 freemem freeswp
   23:59:49     390   88712
   23:59:54     335   88720
   23:59:59     321   88416

Average 349 88732

You may find that your system runs out of swap space before freeswp drops to zero. This is because the operating system requires that enough swap space be available for the grown data and stack regions of all processes, not just those process' pages that have actually been swapped or paged out.

To discover the number of 4KB pages of swappable virtual memory that the operating system calculates is available, use the following command within an interactive crash(ADM) session:

od -d availsmem

For more information about how you can use crash to investigate memory usage, see ``Monitoring memory allocation''.

Next topic: Viewing swapping and paging activity
Previous topic: Viewing physical memory usage

© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003