Re: ZONE_PADDING wastes 4 bytes of the new cacheline

Andrea Arcangeli
2004-10-22T18:42:28Z

On Fri, Oct 22, 2004 at 01:35:27PM +1000, Nick Piggin wrote:
> Andrea do you have any pointers?

here we go, the same that deadlocked 2.4.14pre5aa1 will deadlock 2.6
just now (but not latest mainline 2.4 and of course not any recent
2.4-aa)

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=linux.kernel.3BE07730.60905%40google.com
http://groups.google.com/groups?q=google+VM+deadlock&hl=en&lr=&ie=UTF-8&selm=linux.kernel.20011118092434.A1331%40athlon.random&rnum=1

2.6 has a sysctl that should fix it too but it's disabled by default
(which makes it useless to 99% of userbase) and it's pretty hard to be
able to attempt to tun it to a desired value.

When you get an oom killer triggering too early, or an complete oom
deadlock, I never know if this is the lowmem_reserve missing, or the oom
killer going nuts, and I've a dozen of reports of oom triggering
spurious and some oom deadlock pending. So this is certainly the first
thing I must fix.