Re: fork: out of memory

Craig Schlenter (craig@is.co.za)
Mon, 24 Nov 1997 07:36:53 +0200 (SAT)


> With 2.1.65 I've noticed a couple 'fork: out of memory'
> messages that I think are spurious. At least there was
> plenty of free memory left at the times I got these
> messages. The last time I got it it came from cron's
> run-parts script (I am on a Red Hat 4.2 system) and
> it was mailed to root.
>
> I also got an awk help display on the screen.
>
> Anyone else seen this?

My work machine (a fresh RH 4.2 install with vanilla 2.1.65 added)
exhibited the 'out of memory, can't fork' behaviour on Friday. I have 32M
RAM and 80M swap and I had just installed the K desktop and the standalone
netscape communicator 4.04 ... I had a couple of terminals open (plus
netscape) and that was it - the system locked up and was useless. I had to
hard boot (couldn't telnet in as it couldn't fork a shell for me. I could
ping the box with no larger packet than 800 bytes). I couldn't even switch
back to a VT or control-alt-backspace things ...

I believe it could be a memory fragmentation issue as I find it hard to
believe that 32M RAM + 80M swap is insufficient to do this sort of thing.

There have been several complaints lately to linux-kernel about memory
related issues and the vhand stuff (see linux-mama) does try to address
this but I haven't put that patch in on my work machine yet. The latest
vhand patch turned my home machine (16M RAM) into chewing gum (S L O W
chewing gum) but the prior version was OK btw.

Rik: if you are reading this, kswapd was chomping 99% CPU and I wasn't
trying to do much aside from start netscape. I could watch it paint
xterms, pixel-line by line so I'd guess the new self tuning stuff needs
some more work ...

I've reverted to netscape 3.01 since that seems to chomp less memory and
we'll see how the system holds up (also I'm back on fvwm).

Anyway, just a me-too since I can't exactly figure out how to fix it
myself and I'm hoping someone who can fix it will spot this ;)

Cheers,

--Craig