Hi all.
I was posting about our AlphaServer 2100 4/200 (2 CPU's, 768meg RAM) going
very slow with ~200 users and wondering why. Following observations have
been made:
* System is NOT SWAPPING. I don't think it's swapped once.
So it isn't a virtual memory problem
* On the 'tuned" kernel I was using, at peek times we'd see >90% kernel
load, 0 idle and 9-10% user load. This is wrong. Massive context switches
going on, according to syd >9000/sec.
* With a generic kernel (the only changes being a maxproc uppage and a maxusers
change to reflect our high user loads) this is more like 1500/sec, but
still 80-90% kernel load at peak times.
* Sys performs better with a V3.2A generic kermel than taking options out.
weird. I also compiled with an -O3 as a makeflag rather than a -g as
seems to be the default. Taking profiling out doesn't seem to change
anything.
Anyway the 3.2B CD's arrived today. Annoying that it requires a full re-install
and I can't just do an update (doh!) but maybe that will help with things.
The release notes didn't mention anything about performance though. We can
but hope.
-richard
--
Richard A. Muirden, Sys. Admin |Fan of Shostakovich, "Star Trek" and BOEING!
Mailto: richard_at_rmit.EDU.AU |Fly the Friendly Skies of United Airlines !
Phone: (+61 3) 9660 3814 |I created alt.fan.shostakovich! Fly: UA,AN,WN
http://www.rmit.edu.au/richard |Can *YOU* beat my 114 Shost CD's? :-)
Jolt Can Tower Counter: 17 cans
* 1995: Remembering 20 years since the death of Shostakovich (1906-75) *
Received on Wed Aug 16 1995 - 07:07:47 NZST