collecting kernel metrics (semaphores and shared mem)

[Frank Slootweg]

Please see SAM's Help for these parameters. I.e. select a parameter and then press "Help".

I think your main problem comes from not fully understanding which parameter means what.

Some specific comments:

semmap gives a *warning* if not properly dimensioned, see the Help.

semmns can be the same as semmni, unless semaphore sets (sets of semaphores) are used, which is hardly ever the case.

semmni usage is shown by ipcs(1).

semmnu hardly ever used, but if you want to be sure, set it to semmni/semmns.

shmseg this is a *limit*, you can see the sizes of Shared Memory segments with ipcs(1), so you can see if actual usage is approaching this limit.

shmmni usage is shown by ipcs(1).

[Bryce Nutter]

Larry,

I'm in the same boat as you were 2 years ago and would like to know when I am approaching the point(within 10%) where I need to retune. I'm writing a home-grown script in Patrol to alert when within 10% of certain semaphore and shared memory maximums. What it boils down to is what maximums are output of kmtune that can be seen approaching in ipcs?