Figure 7: Calculating Active Process Table Requirements

A. To use pstat to monitor usage:

# pstat -p | head -1

B. To use crash to monitor usage:

# crash
dumpfile = /dev/kmem, namelist = /sysV68,
outfile = stdout
> proc

Output for this command shows the number of currently defined active process entries. In this case however, the SLOT number does accurately indicate the actual number of active processes.

We can still use the command (proc ! wc -l) which tells crash to run the proc function to display the proc table, but pipe the data through wc -l so we can see the number of lines which are returned. Remember to subtract the required number of lines from the header of the output.

> proc ! wc -l
23
>  quit

C. The Formula

NPROC = ( 2 * number-of-users ) +
number-of-users *
largest-number-of-processes-used )
+ BASE

This calculates the minimum number of entries to have configured in the kernel for the active process table.