Messages in this thread |  | | | Subject | Re: [BUG] fatal hang untarring 90GB file, possibly writeback related. | | From | James Bottomley <> | | Date | Thu, 28 Apr 2011 09:49:43 -0500 |
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On Thu, 2011-04-28 at 08:29 -0400, Chris Mason wrote: > Excerpts from Colin Ian King's message of 2011-04-28 07:36:30 -0400: > > One more data point to add, I've been looking at an identical issue when > > copying large amounts of data. I bisected this - and the lockups occur > > with commit > > 3e7d344970673c5334cf7b5bb27c8c0942b06126 - before that I don't see the > > issue. With this commit, my file copy test locks up after ~8-10 > > iterations, before this commit I can copy > 100 times and don't see the > > lockup. > > Well, that's really interesting. I tried with compaction on here and > couldn't trigger it, but this (very very lightly) tested patch might > help. > > It moves the writeout throttle before the goto restart, and also makes > sure we do at least one cond_resched before we loop.
It seems to take longer, but with a PREEMPT kernel, kswapd eventually shoots up to 99% during the tar.
James
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