Messages in this thread | | | Date | Mon, 22 Jul 2013 18:48:52 +0200 | From | Zlatko Calusic <> | Subject | Re: [patch 0/3] mm: improve page aging fairness between zones/nodes |
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On 19.07.2013 22:55, Johannes Weiner wrote: > The way the page allocator interacts with kswapd creates aging > imbalances, where the amount of time a userspace page gets in memory > under reclaim pressure is dependent on which zone, which node the > allocator took the page frame from. > > #1 fixes missed kswapd wakeups on NUMA systems, which lead to some > nodes falling behind for a full reclaim cycle relative to the other > nodes in the system > > #3 fixes an interaction where kswapd and a continuous stream of page > allocations keep the preferred zone of a task between the high and > low watermark (allocations succeed + kswapd does not go to sleep) > indefinitely, completely underutilizing the lower zones and > thrashing on the preferred zone > > These patches are the aging fairness part of the thrash-detection > based file LRU balancing. Andrea recommended to submit them > separately as they are bugfixes in their own right. >
I have the patch applied and under testing. So far, so good. It looks like it could finally fix the bug that I was chasing few months ago (nicely described in your bullet #3). But, few more days of testing will be needed before I can reach a quality verdict.
Good job! -- Zlatko
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