Re: CPUvps

Steven wrote: > > Hi, > > Got the following on my IDS 7.24UC4X1 on HPUX10.20 (5 CPUs, 9 CPUvps) That's a ratio, if my maths is up to it, of 2 VPs to 1 CPU!!! > pri:informix 23> onstat -g glo|grep cpu > class vps usercpu syscpu total > cpu 9 192149.07 15658.73 207807.80 > vp pid class usercpu syscpu total > 1 20113 cpu 36889.68 3181.98 40071.66 > 3 20129 cpu 46050.40 2896.56 48946.96 > 4 20130 cpu 28517.67 1699.41 30217.08 > 5 20131 cpu 18292.99 1215.59 19508.58 > 6 20132 cpu 11601.74 748.16 12349.90 > 7 20133 cpu 9118.92 1071.51 10190.43 > 8 20135 cpu 17394.67 1923.77 19318.44 > 9 20137 cpu 11906.31 1386.56 13292.87 > 10 20138 cpu 12376.69 1535.19 13911.88 > pri:informix 24> onstat -g sch|grep cpu > vp pid class semops busy waits spins/wait > 1 20113 cpu 168 235 879 > 3 20129 cpu 43 43 1001 > 4 20130 cpu 7 7 1001 > 5 20131 cpu 6 6 1001 > 6 20132 cpu 8 8 1001 > 7 20133 cpu 8 8 1001 > 8 20135 cpu 475 716 847 > 9 20137 cpu 277 396 845 > 10 20138 cpu 423 638 867 > > anyone know of where there seems to be discrepancies in the results under > "onstat -g sch" for vp 3-7? > What I understand under "spins/wait" would translate that these vps seems to > be idling more. Yes. Where's the mystery there? You have 2 VPs running on a CPU, so one is going to be doing the work while the other is idle. A CPU can't physically run more than one process at a time. > Also, under "onstat -g seg" the vps does not seems to have an equal > distribution of workload. would this means that if there is a way to > distribute more evenly, perhaps I can get more performance out of them? Yes, allocate one to one, or less. > btw, previously when I declared 4 cpuvps, and then used "onmode -p +5 cpu", > the results under "onstat -g sch" seems to be more evenly distributed than > what I am getting now. I am sure. The first 4 probably had a break while the new 5 did all the work. The figures would eventually even up, I guess. The general rule for CPU VP allocation is the number of physical CPUs less one, i.e. 5 - 1 = 4. I would stick to that rule on HP, even if this is a database server only. Cheers, -- Mark. +----------------------------------------------------------+-----------+ | Mark D. Stock mailto:mdstock@mydas.freeserve.co.uk |//////// /| | http://www.informix.com http://www.informixhandbook.com |///// / //| | http://www.iiug.org +-----------------------------------+//// / ///| | |What year 2000 bug? year 2000 bug? |/// / ////| | |year 2000 bug? year 2000 bug? year |// / /////| | |2000 bug? year 2000 bug? year 1900 |/ ////////| +----------------------+-----------------------------------+-----------+

> > Yes. Where's the mystery there? You have 2 VPs running on a CPU, so one > is going to be doing the work while the other is idle. A CPU can't > physically run more than one process at a time. > A transputer could, it could run 6 different processes at exactly the same time, just took a little coding effort:-)) -- Paul Watson # WF Software Ltd # You are only young once Tel: +44 1436 674729 # but you can be immature Fax: +44 1436 678693 # for ever www.wfsoftware.com #