Re: Slow database creation and loading
On Jun 19, 8:58 am, "Art S. Kagel" <art.ka...@gmail.com> wrote:
Hi Art,
Thanks for your help with this.
I changed my BUFFERS to 400000 and increased LRUS and CLEANERS to 99
each.
Unfortunately this did not help speed things up. Tonight I am going
to tweak some of the settings that Superboer
suggested. Namely, lowering NUMAIOVPS from 36 to 4 and increasing the
PHYSBUFF and LOGBUFF from 64 to 512 for each.
> Looking at your onstat -p output, I've calculated your critical
> metrics and:
>
> BR = 6.61
> BTR = 81.73
> RAU = 99.990
>
> A Buffwaits Ratio (BR) over 7 means a slow server over 10 is server
> performance death, at 6.61 yours is certainly not optimal. I would
> increase LRUS and CLEANERS (always keep CLEANER >= LRUS) to lower your
> BR. A Buffer Turnover Rate of 81.73 means that you are turning over
> the entire buffer cache almost 82 times an hour or about every 44
> seconds. Ideally BTR should be single digits to get down that low
> you'll have to increase the number of buffers by several times, I'd
> guess that ~400000-500000 would get you below 9. The Readahead
> Utilization (RAU) is fine and should be as close as possible to
> 100.00%, 99.990 is about as good as it gets in practice.
>
> Art S. Kagel
On Jun 21, 9:31 am, johneevo <johne...@gmail.com> wrote:
> On Jun 19, 8:58 am, "Art S. Kagel" <art.ka...@gmail.com> wrote:
>
> Hi Art,
>
> Thanks for your help with this.
>
> I changed my BUFFERS to 400000 and increased LRUS and CLEANERS to 99
> each.
>
> Unfortunately this did not help speed things up. Tonight I am going
> to tweak some of the settings that Superboer
> suggested. Namely, lowering NUMAIOVPS from 36 to 4 and increasing the
> PHYSBUFF and LOGBUFF from 64 to 512 for each.
>
> > Looking at your onstat -p output, I've calculated your critical
> > metrics and:
>
> > BR = 6.61
> > BTR = 81.73
> > RAU = 99.990
>
> > A Buffwaits Ratio (BR) over 7 means a slow server over 10 is server
> > performance death, at 6.61 yours is certainly not optimal. I would
> > increase LRUS and CLEANERS (always keep CLEANER >= LRUS) to lower your
> > BR. A Buffer Turnover Rate of 81.73 means that you are turning over
> > the entire buffer cache almost 82 times an hour or about every 44
> > seconds. Ideally BTR should be single digits to get down that low
> > you'll have to increase the number of buffers by several times, I'd
> > guess that ~400000-500000 would get you below 9. The Readahead
> > Utilization (RAU) is fine and should be as close as possible to
> > 100.00%, 99.990 is about as good as it gets in practice.
>
> > Art S. Kagel
Once you get that all worked out, post the following if it's still not
good:
onstat -p (including the time since stats were zero'd).
onstat -D
onstat -P
onstat -g iov
onstat -F
onstat -R
onstat -g iof
And the update ONCONFIG (or onstat -c output).
We'll see if we can help more.
Art S. Kagel