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* Christoph has movedChristoph Lameter2008-07-04
| | | | | | | | | | | | | | | Remove all clameter@sgi.com addresses from the kernel tree since they will become invalid on June 27th. Change my maintainer email address for the slab allocators to cl@linux-foundation.org (which will be the new email address for the future). Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* slabinfo: Support printout of the number of fallbacksChristoph Lameter2008-05-01
| | | | | | | | | | Add functionality to slabinfo to print out the number of fallbacks that have occurred for each slab cache when the -D option is specified. Also widen the allocation / free field since the numbers became too big after a week. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
* slub: Update statistics handling for variable order slabsChristoph Lameter2008-04-27
| | | | | | | | | | | | | | | | | | | Change the statistics to consider that slabs of the same slabcache can have different number of objects in them since they may be of different order. Provide a new sysfs field total_objects which shows the total objects that the allocated slabs of a slabcache could hold. Add a max field that holds the largest slab order that was ever used for a slab cache. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
* slabinfo: fall back from /sys/kernel/slab to /sys/slabChristoph Lameter2008-02-21
| | | | | | | | | | | | I keep running upstream and mm kernels and the location of the slab directory is different since upstream still uses /sys/slab. This patch makes slabinfo check /sys/slab if /sys/kernel/slab is not there. Makes slabinfo work on any kernel. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* SLUB: Support for performance statisticsChristoph Lameter2008-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The statistics provided here allow the monitoring of allocator behavior but at the cost of some (minimal) loss of performance. Counters are placed in SLUB's per cpu data structure. The per cpu structure may be extended by the statistics to grow larger than one cacheline which will increase the cache footprint of SLUB. There is a compile option to enable/disable the inclusion of the runtime statistics and its off by default. The slabinfo tool is enhanced to support these statistics via two options: -D Switches the line of information displayed for a slab from size mode to activity mode. -A Sorts the slabs displayed by activity. This allows the display of the slabs most important to the performance of a certain load. -r Report option will report detailed statistics on Example (tbench load): slabinfo -AD ->Shows the most active slabs Name Objects Alloc Free %Fast skbuff_fclone_cache 33 111953835 111953835 99 99 :0000192 2666 5283688 5281047 99 99 :0001024 849 5247230 5246389 83 83 vm_area_struct 1349 119642 118355 91 22 :0004096 15 66753 66751 98 98 :0000064 2067 25297 23383 98 78 dentry 10259 28635 18464 91 45 :0000080 11004 18950 8089 98 98 :0000096 1703 12358 10784 99 98 :0000128 762 10582 9875 94 18 :0000512 184 9807 9647 95 81 :0002048 479 9669 9195 83 65 anon_vma 777 9461 9002 99 71 kmalloc-8 6492 9981 5624 99 97 :0000768 258 7174 6931 58 15 So the skbuff_fclone_cache is of highest importance for the tbench load. Pretty high load on the 192 sized slab. Look for the aliases slabinfo -a | grep 000192 :0000192 <- xfs_btree_cur filp kmalloc-192 uid_cache tw_sock_TCP request_sock_TCPv6 tw_sock_TCPv6 skbuff_head_cache xfs_ili Likely skbuff_head_cache. Looking into the statistics of the skbuff_fclone_cache is possible through slabinfo skbuff_fclone_cache ->-r option implied if cache name is mentioned .... Usual output ... Slab Perf Counter Alloc Free %Al %Fr -------------------------------------------------- Fastpath 111953360 111946981 99 99 Slowpath 1044 7423 0 0 Page Alloc 272 264 0 0 Add partial 25 325 0 0 Remove partial 86 264 0 0 RemoteObj/SlabFrozen 350 4832 0 0 Total 111954404 111954404 Flushes 49 Refill 0 Deactivate Full=325(92%) Empty=0(0%) ToHead=24(6%) ToTail=1(0%) Looks good because the fastpath is overwhelmingly taken. skbuff_head_cache: Slab Perf Counter Alloc Free %Al %Fr -------------------------------------------------- Fastpath 5297262 5259882 99 99 Slowpath 4477 39586 0 0 Page Alloc 937 824 0 0 Add partial 0 2515 0 0 Remove partial 1691 824 0 0 RemoteObj/SlabFrozen 2621 9684 0 0 Total 5301739 5299468 Deactivate Full=2620(100%) Empty=0(0%) ToHead=0(0%) ToTail=0(0%) Descriptions of the output: Total: The total number of allocation and frees that occurred for a slab Fastpath: The number of allocations/frees that used the fastpath. Slowpath: Other allocations Page Alloc: Number of calls to the page allocator as a result of slowpath processing Add Partial: Number of slabs added to the partial list through free or alloc (occurs during cpuslab flushes) Remove Partial: Number of slabs removed from the partial list as a result of allocations retrieving a partial slab or by a free freeing the last object of a slab. RemoteObj/Froz: How many times were remotely freed object encountered when a slab was about to be deactivated. Frozen: How many times was free able to skip list processing because the slab was in use as the cpuslab of another processor. Flushes: Number of times the cpuslab was flushed on request (kmem_cache_shrink, may result from races in __slab_alloc) Refill: Number of times we were able to refill the cpuslab from remotely freed objects for the same slab. Deactivate: Statistics how slabs were deactivated. Shows how they were put onto the partial list. In general fastpath is very good. Slowpath without partial list processing is also desirable. Any touching of partial list uses node specific locks which may potentially cause list lock contention. Signed-off-by: Christoph Lameter <clameter@sgi.com>
* kset: move /sys/slab to /sys/kernel/slabGreg Kroah-Hartman2008-01-24
| | | | | | | | | | /sys/kernel is where these things should go. Also updated the documentation and tool that used this directory. Cc: Kay Sievers <kay.sievers@vrfy.org> Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation/vm/slabinfo.c: clean up this codeWANG Cong2007-10-17
| | | | | | | | | | | | | | | This patch does the following cleanups for Documentation/vm/slabinfo.c: - Fix two memory leaks; - Constify some char pointers; - Use snprintf instead of sprintf in case of buffer overflow; - Fix some indentations; - Other little improvements. Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SLUB: Fix format specifier in Documentation/vm/slabinfo.cJesper Juhl2007-08-10
| | | | | | | | | There's a little problem in Documentation/vm/slabinfo.c The code is using "%d" in a printf() call to print an 'unsigned long'. This patch corrects it to use "%lu" instead. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Christoph Lameter <clameter@sgi.com>
* slub: another slabinfo fixChristoph Lameter2007-05-18
| | | | | | | | | The slab manipulation functions should not be triggered by slabs that are unresovable in the subset of slabs selected on the command line. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SLUB: slabinfo fixesChristoph Lameter2007-05-17
| | | | | | | | | | | | | Align the output of % with K/M/G of sizes. Check for empty NUMA information to avoid segfault on !NUMA. -r should work directly not only if we match a single slab without additional options. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SLUB: slabinfo upgradeChristoph Lameter2007-05-09
| | | | | | | | | | | | | -e Show empty slabs -d Modification of slab debug options at runtime -o Operations. Display of ctor / dtor etc. -r Report: Display all available information about a slabcache. Cleanup tracking display and make it work right. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* slub: add slabinfo toolChristoph Lameter2007-05-07
Add the tool which gets reports about slabs to the VM documentation directory. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>