Re: [BUG] 2.4 VM sucks. Again

Martin J. Bligh
2002-05-23T16:45:46Z

>> > Starting up 30 downloads from a custom HTTP server (or Tux - or Apache -
>> > doesn't matter), file size is 3-6GB, download speed = ~4.5Mbps. After
>> > some time the kernel (a) goes bOOM (out of memory) if not having any
>> > swap, or (b) goes gong swapping out anything it can.
>>
>> How much RAM do you have, and what does /proc/meminfo
>> and /proc/slabinfo say just before the explosion point?
>
> I have 1 gig - highmem (not enabled) - 900 megs.
> for what I can see, kernel can't reclaim buffers fast enough.
> ut looks better on -aa.

Sounds like exactly the same problem we were having. There are two
approaches to solving this - Andrea has a patch that tries to free them
under memory pressure, akpm has a patch that hacks them down as soon
as you've fininshed with them (posted to lse-tech mailing list). Both approaches
seemed to work for me, but the performance of the fixes still has to be established.

I've seen over 1Gb of buffer_heads ;-)

M.