Re: NUMCPUVPS
Posted in 2000
mmmmm
In addtion to what the others said....
Are you running KAIO?
If you are do the following
echo "_ncols/D"|adb -k /stand/vmunix /dev/kmem
If this going up at all be worried, if it's going up real fast be very
worried. It measures the number of collisions ie the number of times
all your CPUVP's have been woken up to perform IO (if your using KAIO)
the high end HP's seem to hit a brick wall at certain load levels
because of this, switch to AIO VP's and the problem goes away.
cheers
mja
In article <39A40185.2C236948@wholefoods.com>,
Phillip <tienp@wholefoods.com> wrote:
> According to the manuals, NUMCPUVPS should be one less than actual
physical
> CPUs. If you have 6 physical CPUs, set NUMCPUVPS to 5. You should
check the
> cache hit ratios for both read and write when you do an onstat -p as
this will
> tell you if you're having a lot of I/O. For OLTP environments, read
ratios
> should be >=95% and write ratios should be >=85%. If numbers are
less than
> this, that means too much activity is going to and from disk rather
than being
> done in memory. If that's the case, you should tune your shared
memory
> parameters (BUFFERS, LRUs, CLEANERS, etc.).
>
> Masa wrote:
>
> > We have a two server cluster environment. Another server is for Baan
> > application and another is for Informix database.
> > Informix version is 7.31 FC2. Both servers are HP N 4000 (6 CPU)
with HP-UX
> > 11.0.
> >
> > Now users are reported to us that application is getting slower.
> >
> > Application server runs 50-60% Idle time almost whole day. Database
server
> > runs only 10-15 % Idle time during rush ours.
> > Oninit processes are first on top listing.
> >
> >
************************************************************************
****
> >
> > What is the right value for parameter NUMCPUVPS ?
> >
> > Now is is same as physical processor number (6)
> >
> > There are two onstat listings. (measuring interval 3670 sec)
> > Onstat -p
> >
> > Up 2 days 23:58:56
> > ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes
> > 0 0 0 39043.25 109627.06 1957 4274
> >
> > Up 3 days 01:00:06
> > ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes
> > 0 0 0 41719.61 121013.40 1987 4334
> >
> > Thanks for your advice!
>
> --
> Phillip Tien
> Database Administrator
> Whole Foods Market, Inc.
>
> "I always wanted to be the last guy on Earth just to see if all those
women were
> lying to me."
>
>
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