RE: CPU Time slices, technotes.

Hi Stephen, The system that we were testing on had 8 CPUs and was 10.1 or 10.2. We configured 16 CPUVPS and it ran MUCH faster. I have no input for your timeslice question. The point of the article was not to trust what you read but to experiment. Every system is different and requires individual exploration. Good news for us that like to tinker, bad news for those that prefer set formulas. Enjoy, Bill -----Original Message----- From: Stephen_Murray@agsea.com [mailto:Stephen_Murray@agsea.com] Sent: Tuesday, November 30, 1999 10:17 AM To: informix-list@iiug.org Cc: bill@bamph.com Subject: Re: CPU Time slices, technotes. What timeslice value is recommended for HP-UX 10.20? The default is 10 ticks. Ticks are 10ms each, so effectively the default is 100ms or 1/10s, same as the Sun default. HP 10.20 comes with a parameter template called "database server" (or something similar) which, among other changes, sets the timeslice down to 1. I have a Lawson consultant telling me that I really should have the timeslice at the default of 10. Along the same lines, I recently read an Informix TechInfo article by William Burton which recommends for 2 CPU VPs per physical CPU for HP systems with up to 4 processors. Does anyone have any experience with this? Does anyone know of further details such as: Platform (We have a K580's, K200's, K210's and K220's and are considering an N or V series) OS version (10.20 or 11.0) timeslice parameter value "Art S. Kagel" <kagel@bloomberg.net> on 02/18/99 12:02:26 PM Please respond to kagel@bloomberg.net To: informix-list@iiug.org cc: (bcc: Stephen Murray/AGInc) Subject: Re: CPU Time slices, technotes. David Tamburin wrote: > > This is a multi-part message in MIME format. > A few days ago I saw a message by Art S. Kagel. It mentioned changing > some kernal parameters to change timeslice to improve performance. > Could anyone tell me where I can dig this information up? OK Here are the Kernel parameters to adjust the Solaris system clock and timeslice down form the default 1/10 sec to 1ms. In /etc/system: set hires_tick=1 # or 2 - Number of system ticks per timeslice- 1 ms set hires_hz=1000 # Number of system ticks per second, ie set to ms Without this change you will be hard pressed to push the machine beyond about 65% utilization. After the change you can add processes and push utilization above 92%! Art S. Kagel