Messages in this thread | | | Date | Mon, 7 Jan 2008 14:32:17 -0500 | From | Rik van Riel <> | Subject | Re: [patch 00/19] VM pageout scalability improvements |
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On Mon, 7 Jan 2008 11:07:54 -0800 (PST) Christoph Lameter <clameter@sgi.com> wrote: > On Fri, 4 Jan 2008, Lee Schermerhorn wrote: > > > We see this on both NUMA and non-NUMA. x86_64 and ia64. The basic > > criteria to reproduce is to be able to run thousands [or low 10s of > > thousands] of tasks, continually increasing the number until the system > > just goes into reclaim. Instead of swapping, the system seems to > > hang--unresponsive from the console, but with "soft lockup" messages > > spitting out every few seconds... > > Ditto here.
I have some suspicions on what could be causing this.
The most obvious suspect is get_scan_ratio() continuing to return 100 file reclaim, 0 anon reclaim when the file LRUs have already been reduced to something very small, because reclaiming up to that point was easy.
I plan to add some code to automatically set the anon reclaim to 100% if (free + file_active + file_inactive <= zone->pages_high), meaning that reclaiming just file pages will not be able to free enough pages.
-- All rights reversed.
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