This series is related to the new addition to stable_kernel_rules.txt - Serious issues as reported by a user of a distribution kernel may also be considered if they fix a notable performance or interactivity issue. As these fixes are not as obvious and have a higher risk of a subtle regression they should only be submitted by a distribution kernel maintainer and include an addendum linking to a bugzilla entry if it exists and additional information on the user-visible impact. All of these patches have been backported to a distribution kernel and address some sort of performance issue in the VM. As they are not all obvious, I've added a "Stable note" to the top of each patch giving additional information on why the patch was backported. Lets see where the boundaries lie on how this new rule is interpreted in practice :). Patch 1 Performance fix for tmpfs Patch 2 Memory hotadd fix Patch 3 Reduce boot time on large machines Patches 4-5 Reduce stalls for wait_iff_congested Patches 6-8 Reduce excessive reclaim of slab objects which for some workloads will reduce the amount of IO required Patches 9-10 limits the amount of page reclaim when THP/Compaction is active. Excessive reclaim in low memory situations can lead to stalls some of which are user visible. Patches 11-19 reduce the amount of churn of the LRU lists. Poor reclaim decisions can impair workloads in different ways and there have been complaints recently the reclaim decisions of modern kernels are worse than older ones. Patches 20-21 reduce the amount of CPU kswapd uses in some cases. This is harder to trigger but were developed due to bug reports about 100% CPU usage from kswapd. Patches 22-25 are mostly related to interactivity when THP is enabled. Patches 26-30 are also related to page reclaim decisions, particularly the residency of mapped pages. Patches 31-34 fix a major page allocator performance regression All of the patches will apply to 3.0-stable but the ordering of the patches is such that applying them to 3.2-stable and 3.4-stable should be straight-forward. I am bending or breaking the rules in places that needs examination. 1. Not all these patches have a bugzilla entry because in many cases I was doing the investigation based on my own testing. By rights, I should have been creating bugzilla entries for each of them but there only are so many hours in the day. 2. I will be duplicated in the signed-offs because I may both the author of the patch and now part of the submission path to -stable. I don't think there is anything wrong with this but it might look weird to some people. 3. Some patches are in the series only because they make later patches easier to backport. 4. Patch 30 stomps all over the rules. The upstream patch accidentally fixes a problem and was found through bisection but the full patch and the series itself is not a good -stable candidate. I'm running tests against the backport as it's a unique combination but the patches have been tested as part of the distribution backport already. It'll be a few days before I have an exact comparison between 3.0.36 and the backport but I have a few basic results against 3.0.23. I'm not going to analyse them in detail but here a few points http://www.csn.ul.ie/~mel/postings/stableport-20120719/global-dhp__pagealloc-performance/hydra/comparison.html o System CPU time reduced on kernbench o Page allocator latency reduced for the most part, there are counter-examples but it's mostly reduced o page_test, brk_test improved on aim9 o 5% gain in page faults/sec in page fault micro benchmark http://www.csn.ul.ie/~mel/postings/stableport-20120719/global-dhp__pagereclaim-performance-ext4/hydra/comparison.html o fsmark in single threaded mode completed faster and with higher operations/second o postmark looks slower but there are changes in ext4 between 3.0.23 and 3.0.36 that might account for this. kswapd scan rates were slightly reduced o In the micro benchmark, it took longer to complete but kswapd and direct reclaim activity were reduced Alex,Shi (2): kswapd: avoid unnecessary rebalance after an unsuccessful balancing kswapd: assign new_order and new_classzone_idx after wakeup in sleeping Dave Chinner (3): vmscan: add shrink_slab tracepoints vmscan: shrinker->nr updates race and go wrong vmscan: reduce wind up shrinker->nr when shrinker can't do work David Rientjes (2): cpusets: avoid looping when storing to mems_allowed if one node remains set cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask Dimitri Sivanich (1): mm: vmstat: cache align vm_stat Hugh Dickins (1): mm: test PageSwapBacked in lumpy reclaim Johannes Weiner (1): mm: vmscan: fix force-scanning small targets without swap Konstantin Khlebnikov (3): vmscan: promote shared file mapped pages vmscan: activate executable pages after first usage mm/hugetlb: fix warning in alloc_huge_page/dequeue_huge_page_vma Mel Gorman (14): mm: memory hotplug: Check if pages are correctly reserved on a per-section basis mm: Reduce the amount of work done when updating min_free_kbytes mm: Abort reclaim/compaction if compaction can proceed mm: migration: clean up unmap_and_move() mm: compaction: Allow compaction to isolate dirty pages mm: compaction: Determine if dirty pages can be migrated without blocking within ->migratepage mm: page allocator: Do not call direct reclaim for THP allocations while compaction is deferred mm: compaction: make isolate_lru_page() filter-aware again mm: compaction: Introduce sync-light migration for use by compaction mm: vmscan: When reclaiming for compaction, ensure there are sufficient free pages available mm: vmscan: Do not OOM if aborting reclaim to start compaction mm: vmscan: Check if reclaim should really abort even if compaction_ready() is true for one zone mm: vmscan: Do not force kswapd to scan small targets cpuset: mm: Reduce large amounts of memory barrier related damage v3 Minchan Kim (5): mm: compaction: trivial clean up in acct_isolated() mm: change isolate mode from #define to bitwise type mm: compaction: make isolate_lru_page() filter-aware mm: zone_reclaim: make isolate_lru_page() filter-aware mm/vmscan.c: consider swap space when deciding whether to continue reclaim Rik van Riel (1): mm: limit direct reclaim for higher order allocations Shaohua Li (1): vmscan: clear ZONE_CONGESTED for zone with good watermark .../trace/postprocess/trace-vmscan-postprocess.pl | 8 +- drivers/base/memory.c | 58 ++-- fs/btrfs/disk-io.c | 5 +- fs/hugetlbfs/inode.c | 3 +- fs/nfs/internal.h | 2 +- fs/nfs/write.c | 4 +- include/linux/cpuset.h | 45 ++-- include/linux/fs.h | 11 +- include/linux/init_task.h | 8 + include/linux/memcontrol.h | 3 +- include/linux/migrate.h | 23 +- include/linux/mmzone.h | 14 + include/linux/sched.h | 2 +- include/linux/swap.h | 7 +- include/trace/events/vmscan.h | 85 +++++- kernel/cpuset.c | 63 ++--- kernel/fork.c | 3 + mm/compaction.c | 26 +- mm/filemap.c | 11 +- mm/hugetlb.c | 13 +- mm/memcontrol.c | 3 +- mm/memory-failure.c | 2 +- mm/memory_hotplug.c | 2 +- mm/mempolicy.c | 30 ++- mm/migrate.c | 224 ++++++++++------ mm/page_alloc.c | 113 +++++--- mm/slab.c | 13 +- mm/slub.c | 39 ++- mm/vmscan.c | 280 ++++++++++++++++---- mm/vmstat.c | 2 +- 30 files changed, 772 insertions(+), 330 deletions(-) -- 1.7.9.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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