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Here's the next round of these patches. These are totally different in an attempt to meet the "simpler" request after the last patches. For reference the earlier threads are: http://marc.theaimsgroup.com/?l=linux-kernel&m=110839604924587&w=2 http://marc.theaimsgroup.com/?l=linux-mm&m=111461480721249&w=2 This set of patches replaces my other vm- patches that are currently in -mm. So they're against 2.6.12-rc5-mm1 about half way through the -mm patchset. As I said already this patch is a lot simpler. The reclaim is turned on or off on a per-zone basis using a syscall. I haven't tested the x86 syscall, so it might be wrong. It uses the existing reclaim/pageout code with the small addition of a may_swap flag to scan_control (patch 1/4). I also added __GFP_NORECLAIM (patch 3/4) so that certain allocation types can be flagged to never cause reclaim. This was a deficiency that was in all of my earlier patch sets. Previously, doing a big buffered read would fill one zone with page cache and then start to reclaim from that same zone, leaving the other zones untouched. Adding some extra throttling on the reclaim was also required (patch 4/4). Without the machine would grind to a crawl when doing a "make -j" kernel build. Even with this patch the System Time is higher on average, but it seems tolerable. Here are some numbers for kernbench runs on a 2-node, 4cpu, 8Gig RAM Altix in the "make -j" run: wall user sys %cpu ctx sw. sleeps ---- ---- --- ---- ------ ------ No patch 1009 1384 847 258 298170 504402 w/patch, no reclaim 880 1376 667 288 254064 396745 w/patch & reclaim 1079 1385 926 252 291625 548873 These numbers are the average of 2 runs of 3 "make -j" runs done right after system boot. Run-to-run variability for "make -j" is huge, so these numbers aren't terribly useful except to seee that with reclaim the benchmark still finishes in a reasonable amount of time. I also looked at the NUMA hit/miss stats for the "make -j" runs and the reclaim doesn't make any difference when the machine is thrashing away. Doing a "make -j8" on a single node that is filled with page cache pages takes 700 seconds with reclaim turned on and 735 seconds without reclaim (due to remote memory accesses). The simple zone_reclaim syscall program is at http://www.bork.org/~mort/sgi/zone_reclaim.c This patch: This adds an extra switch to the scan_control struct. It simply lets the reclaim code know if its allowed to swap pages out. This was required for a simple per-zone reclaimer. Without this addition pages would be swapped out as soon as a zone ran out of memory and the early reclaim kicked in. Signed-off-by: Martin Hicks <mort@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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| .. | ||
| bootmem.c | ||
| fadvise.c | ||
| filemap.c | ||
| fremap.c | ||
| highmem.c | ||
| hugetlb.c | ||
| internal.h | ||
| madvise.c | ||
| Makefile | ||
| memory.c | ||
| mempolicy.c | ||
| mempool.c | ||
| mincore.c | ||
| mlock.c | ||
| mmap.c | ||
| mprotect.c | ||
| mremap.c | ||
| msync.c | ||
| nommu.c | ||
| oom_kill.c | ||
| page_alloc.c | ||
| page_io.c | ||
| page-writeback.c | ||
| pdflush.c | ||
| prio_tree.c | ||
| readahead.c | ||
| rmap.c | ||
| shmem.c | ||
| slab.c | ||
| swap_state.c | ||
| swap.c | ||
| swapfile.c | ||
| thrash.c | ||
| tiny-shmem.c | ||
| truncate.c | ||
| vmalloc.c | ||
| vmscan.c | ||