Odd Memory problem: SA NOT using available memory

[JOW]

I'm out of my element on this, so please forgive me if I ask something silly.

We have two SpamAssassin (v3.002003) servers on Red Hat, each with 4gb RAM.  ServerA ROCKS while ServerB SUCKS.

So I've been comparing the two systems hoping to find some configuration differences between them.

When I do a vmstat, I see a couple of things that are glaringly different:
ServerA
procs                      memory      swap          io     system         cpu
 r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us sy id wa
 0  0      0 354012 154360 3395248    0    0     1     6    6     1  1  2  4  8

ServerB
procs                      memory      swap          io     system         cpu
 r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us sy id wa
 1  0      0 3831400  73308 148168    0    0     3   184  108   325 18  3 68 11

ServerA (the good one) is using nearly all of the 4gb of RAM available to it.
But ServerB is only using a fraction of available RAM and the # of context switches is tons higher, too.

I hope this isn't a silly question, but how significant is this, and where do I go from here?

Thanks for any help,
Joe

[Matus UHLAR - fantomas]

On 28.09.07 14:06, JOW wrote:
> I'm out of my element on this, so please forgive me if I ask something silly.
>
> We have two SpamAssassin (v3.002003) servers on Red Hat, each with 4gb RAM.
> ServerA ROCKS while ServerB SUCKS.

> ServerA (the good one) is using nearly all of the 4gb of RAM available to
> it. But ServerB is only using a fraction of available RAM and the # of
> context switches is tons higher, too.

that is not a thing SA controls. The usage of memory depends on OS.
SpamAssassin uses as much memory as it needs, unless there's memory leak in
it or in libraries SA uses. But in such case, that memory is wasted.

--
Matus UHLAR - fantomas, uhlar@... ; http://www.fantomas.sk/
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
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[John Hardin]

On Fri, 28 Sep 2007, JOW wrote:

> ServerA (the good one) is using nearly all of the 4gb of RAM
> available to it. But ServerB is only using a fraction of available
> RAM and the # of context switches is tons higher, too.
>
> I hope this isn't a silly question, but how significant is this,
> and where do I go from here?

Are they both running the same kernel? The kernel on server B may have
been compiled with different memory config options thatn the one on
server A.

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 John Hardin KA7OHZ                    http://www.impsec.org/~jhardin/
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[JOW]

Thanks for the quick reply.

So I shouldn't read anything into the disparity of memory usage between the two boxes?

I'm at a loss as to why the one box is consistently in distress, while the other is consistently doing great.

I should have mentioned we're using spamd (-m 50) and I've compared the main.cf's and found no differences.  Seems like there must be something I'm missing though for these servers to behave so differently.

Thanks again for the quick response, and any additional help,
Joe

[JOW]

From a uname -v, they both appear to be #1 SMP Fri Oct 13 17:56:20 EDT 2006.

Here's a uname -a on each:
ServerB (B as in bad):
Linux expurgate2 2.4.21-47.0.1.ELsmp #1 SMP Fri Oct 13 17:56:20 EDT 2006 i686 i686 i386 GNU/Linux

ServerA (A as in awesome):
Linux expurgate1 2.4.21-47.0.1.ELsmp #1 SMP Fri Oct 13 17:56:20 EDT 2006 i686 i686 i386 GNU/Linux

I asked one of our Unix admins that very question, but he unfortunately is not the one who built the servers, and didn't know.  Is there any way to tell now if they were compiled with different memory config options, or does the fact that they have the same kernel version eliminate that possibility?

Thanks John

[Loren Wilton]

> So I shouldn't read anything into the disparity of memory usage between
> the
> two boxes?

Check the number of SA children configured.  Maybe you have the bad box
limited to 1 or 2 children or some such.

        Loren

>
> I'm at a loss as to why the one box is consistently in distress, while the
> other is consistently doing great.
>
> I should have mentioned we're using spamd (-m 50) and I've compared the
> main.cf's and found no differences.  Seems like there must be something
> I'm
> missing though for these servers to behave so differently.
>
> Thanks again for the quick response, and any additional help,
> Joe
> --
> View this message in context:
> http://www.nabble.com/Odd-Memory-problem%3A-SA-NOT-using-available-memory-tf4536780.html#a12948922
> Sent from the SpamAssassin - Users mailing list archive at Nabble.com.