Hi,
> A 997/800
> 380GB of disc
> 700+ active online users
> 45 jobs at any given time
>
> The system spends on AVERAGE 9% cpu on memory management, that means
> there are extended periods where the system spends over 20% CPU on
> memory management for hours at a time.

First, is there a performance problem?

Sure...there are some stated oddities about how much CPU is spent
of memory management...but that only matters if there's a performance problem!

What's the "speedometer" show (control-B on ldev 20), on average, over a
few minutes?  If it's 70 (F7FF) or less, then you aren't CPU bound ...
can probably afford that extra CPU usage.

> Page fault rate on average over a 24 hour period is 60 per second, but
> it is not uncommon to be over 100 per second. (slightly lower than I
> would expect)

Depending upon locality, there's a chance that adding more memory might
drop that page fault rate, which would increase pressure on the CPU.
(Also, adding more memory might increase memory manager overhead.)

If the data locality isn't great, then adding more memory might not affect
the page fault rate ... so no benefit, but it *could* increase MM overhead
(bad).  That would be the primary scenario where adding more memory could hurt.

> What I find amazing is that not only is HP telling them that Memory will
> only make the matters worse, but that adding more CPU's will also not
> help.

We can't tell from the data presented so far.

Stan
Stan Sieler                                           [log in to unmask]
www.allegro.com/sieler/wanted/index.html          www.allegro.com/sieler

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