From 47ba87e0b1269698801310bfd1716b0538282405 Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Fri, 3 Feb 2006 03:04:06 -0800 Subject: [PATCH] make "struct d_cookie" depend on CONFIG_PROFILING Shrinks "struct dentry" from 128 bytes to 124 on x86, allowing 31 objects per slab instead of 30. Cc: John Levon Cc: Philippe Elie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/dcache.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/dcache.c') diff --git a/fs/dcache.c b/fs/dcache.c index 86bdb93789c6..a173bba32666 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -743,7 +743,9 @@ struct dentry *d_alloc(struct dentry * parent, const struct qstr *name) dentry->d_op = NULL; dentry->d_fsdata = NULL; dentry->d_mounted = 0; +#ifdef CONFIG_PROFILING dentry->d_cookie = NULL; +#endif INIT_HLIST_NODE(&dentry->d_hash); INIT_LIST_HEAD(&dentry->d_lru); INIT_LIST_HEAD(&dentry->d_subdirs); -- cgit v1.2.3 From 529bf6be5c04f2e869d07bfdb122e9fd98ade714 Mon Sep 17 00:00:00 2001 From: Dipankar Sarma Date: Tue, 7 Mar 2006 21:55:35 -0800 Subject: [PATCH] fix file counting I have benchmarked this on an x86_64 NUMA system and see no significant performance difference on kernbench. Tested on both x86_64 and powerpc. The way we do file struct accounting is not very suitable for batched freeing. For scalability reasons, file accounting was constructor/destructor based. This meant that nr_files was decremented only when the object was removed from the slab cache. This is susceptible to slab fragmentation. With RCU based file structure, consequent batched freeing and a test program like Serge's, we just speed this up and end up with a very fragmented slab - llm22:~ # cat /proc/sys/fs/file-nr 587730 0 758844 At the same time, I see only a 2000+ objects in filp cache. The following patch I fixes this problem. This patch changes the file counting by removing the filp_count_lock. Instead we use a separate percpu counter, nr_files, for now and all accesses to it are through get_nr_files() api. In the sysctl handler for nr_files, we populate files_stat.nr_files before returning to user. Counting files as an when they are created and destroyed (as opposed to inside slab) allows us to correctly count open files with RCU. Signed-off-by: Dipankar Sarma Cc: "Paul E. McKenney" Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/dcache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/dcache.c') diff --git a/fs/dcache.c b/fs/dcache.c index a173bba32666..11dc83092d4a 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1736,7 +1736,7 @@ void __init vfs_caches_init(unsigned long mempages) SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL); filp_cachep = kmem_cache_create("filp", sizeof(struct file), 0, - SLAB_HWCACHE_ALIGN|SLAB_PANIC, filp_ctor, filp_dtor); + SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL); dcache_init(mempages); inode_init(mempages); -- cgit v1.2.3