Messages in this thread | | | Date | Thu, 12 Jun 2008 01:16:51 -0700 | From | Andrew Morton <> | Subject | Re: repeatable slab corruption with LTP msgctl08 |
| |
On Thu, 12 Jun 2008 01:15:37 -0700 Andrew Morton <akpm@linux-foundation.org> wrote:
> On Thu, 12 Jun 2008 01:02:00 -0700 Andrew Morton <akpm@linux-foundation.org> wrote: > > > On Wed, 11 Jun 2008 23:34:49 -0700 Andrew Morton <akpm@linux-foundation.org> wrote: > > > > > On Wed, 11 Jun 2008 22:13:24 -0700 Andrew Morton <akpm@linux-foundation.org> wrote: > > > > > > > Running current mainline on my old 2-way PIII. Distro is RH FC1. LTP > > > > version is ltp-full-20070228 (lots of retro-computing there). > > > > > > > > Config is at http://userweb.kernel.org/~akpm/config-vmm.txt > > > > > > > > > > > > ./testcases/bin/msgctl08 crashes after ten minutes or so: > > > > > > ah, it runs to completion in about ten seconds on 2.6.25, so it'll be > > > easy for someone to bisect it. > > > > > > What's that? Sigh. OK. I wasn't doing anything much anyway. > > > > Oh drat. git-bisect tells me that this one-year-old msgctl08's > > execution time vastly increased when we added > > > > commit f7bf3df8be72d98afa84f5ff183e14c1ba1e560d > > Author: Nadia Derbey <Nadia.Derbey@bull.net> > > Date: Tue Apr 29 01:00:39 2008 -0700 > > > > ipc: scale msgmni to the amount of lowmem > > > > > > But we already knew that, and LTP got changed to fix it. > > > > So I was wrong in assuming that the long-execution-time correlates with > > the slab-corruption bug. > > > > And the slab corruption bug takes half an hour to reproduce and an > > unknown amount of time to not-reproduce. I don't think I'll be able to > > complete this before I disappear for over a week. > > > > Doing > > echo 16 > /proc/sys/kernel/msgmni > > on the tree at the above bisection point > (f7bf3df8be72d98afa84f5ff183e14c1ba1e560d is most-recently-applied > patch), msgctl08 runs to completion in 15.7 seconds. > > Doing the same thing on 2.6.26-rc5-mm3, msgctl08 also runs to > completion, in 20.9 seconds. So > > - it got slower > > - the crash requires the huge value of /proc/sys/kernel/msgmni (1746)
actually, it's 1741.
> to reproduce. >
| |