Re: NUMCPUVPS settings for a four-processor server

In article <6ck1q1$p40@drn.newsguy.com>, Neil Truby <?@?.?> writes >I'm migrating two Informix database servers to a Sun Ultra E4002 with 1.5 GBytes >of memory and 4CPUs. One server is heavily-used and performance is optimal, the >other is lightly used. > >I am planning to set up the heavily-used server with NUMCPUVPS=3 (one less than >the actual number of processors) as per various recommendations, and leaving the >other server with NUMCPUVPS=1. > >Anyone have any other views about NUMCPUVPS settings, and about the use of Sounds reasonable to me, altough if onstat -g glo shows that CPU usage is high and onstat -g rea shows you have threads waiting for the CPU I might go for NUMCPUVPS=4. SOME people, mainly data warehouse people run with NUMCPUVPS = Number ^^^^ ^^^^ of physical CPUS!!! Personable I'd rather keep the busy and quiet systems apart. >processor affinity? > Affine them both, making sure the quiet one starts at cpu 1 and the other at CPU 2. on some versions of UNIX 'system' type things e.g. timer interrupts only go to the first cpu. >Thanks > >Neil Truby >Chase Manhattan Bank >Bournemouth, UK >neil.truby@chase.com > >P.S. I know that I would probably optimise performance by having a single server >with multiple databases; however for reasons outside my control this has been >ruled out. -- David Williams Maintainer of the Informix FAQ Primary site (Beta Version) http://www.smooth1.demon.co.uk Official site http://www.iiug.org/techinfo/faq/faq_top.html I see you standin', Standin' on your own, It's such a lonely place for you, For you to be If you need a shoulder, Or if you need a friend, I'll be here standing, Until the bitter end... So don't chastise me Or think I, I mean you harm... All I ever wanted Was for you To know that I care