Roy Sigurd Karlsbakk wrote:
>
> On Tue, 28 Aug 2001, Andrew Morton wrote:
>
> > Possibly, VM system changes have taken you over some threshold.
> > Are you putting a lot of traffic through that machine?
>
> There's <= 2500 messages (sendmail - usually <5 concurrently) going
> through per day, some 10.000 pop connections per day (mostly at working
> hours). The server's got some 256 megs of RAM, and is doing some small
> databases with postgresql and mysql in addition to the apache server. The
> server does not have any problems with swapping, as the text below should
> show.
>
> As far as I can see from linux/mm/swap.c, it shouldn't have anything to do
> with freepages... Am I wrong?
>
> roy
>
> [root@server log]# free
> total used free shared buffers cached
> Mem: 257876 252976 4900 64120 65156 147368
> -/+ buffers/cache: 40452 217424
> Swap: 136512 268 136244
>
Networking needs to allocate memory at interrupt time. This is
referred to as "atomic allocation". The only way in which this
can be successful is for the VM system to ensure that there is
a pool of immediately-allocatable memory lying around.
The 2.2 kernel uses the tunables in /proc/sys/vm/freepages to
decide how large that pool should be. Machines which sustain
a high network load commonly require more memory than the
default freepages setting provides. People who encounter network
Rx allocation failures with 2.2 kernels do report that increasing
the freepages tunables fixes the problem.
-
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Aug 31 2001 - 21:00:30 EST