From 138211515c102807a16c02fdc15feef1f6ef8124 Mon Sep 17 00:00:00 2001 From: Tao Ma Date: Wed, 25 Feb 2009 00:53:23 +0800 Subject: ocfs2: Optimize inode allocation by remembering last group In ocfs2, the inode block search looks for the "emptiest" inode group to allocate from. So if an inode alloc file has many equally (or almost equally) empty groups, new inodes will tend to get spread out amongst them, which in turn can put them all over the disk. This is undesirable because directory operations on conceptually "nearby" inodes force a large number of seeks. So we add ip_last_used_group in core directory inodes which records the last used allocation group. Another field named ip_last_used_slot is also added in case inode stealing happens. When claiming new inode, we passed in directory's inode so that the allocation can use this information. For more details, please see http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy. Signed-off-by: Tao Ma Signed-off-by: Mark Fasheh --- fs/ocfs2/suballoc.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/ocfs2/suballoc.h') diff --git a/fs/ocfs2/suballoc.h b/fs/ocfs2/suballoc.h index e3c13c77f9e8..ea85a4c8b4b1 100644 --- a/fs/ocfs2/suballoc.h +++ b/fs/ocfs2/suballoc.h @@ -88,6 +88,8 @@ int ocfs2_claim_metadata(struct ocfs2_super *osb, u64 *blkno_start); int ocfs2_claim_new_inode(struct ocfs2_super *osb, handle_t *handle, + struct inode *dir, + struct buffer_head *parent_fe_bh, struct ocfs2_alloc_context *ac, u16 *suballoc_bit, u64 *fe_blkno); -- cgit v1.2.2 From 6ca497a83e592d64e050c4d04b6dedb8c915f39a Mon Sep 17 00:00:00 2001 From: wengang wang Date: Fri, 6 Mar 2009 21:29:10 +0800 Subject: ocfs2: fix rare stale inode errors when exporting via nfs For nfs exporting, ocfs2_get_dentry() returns the dentry for fh. ocfs2_get_dentry() may read from disk when the inode is not in memory, without any cross cluster lock. this leads to the file system loading a stale inode. This patch fixes above problem. Solution is that in case of inode is not in memory, we get the cluster lock(PR) of alloc inode where the inode in question is allocated from (this causes node on which deletion is done sync the alloc inode) before reading out the inode itsself. then we check the bitmap in the group (the inode in question allcated from) to see if the bit is clear. if it's clear then it's stale. if the bit is set, we then check generation as the existing code does. We have to read out the inode in question from disk first to know its alloc slot and allot bit. And if its not stale we read it out using ocfs2_iget(). The second read should then be from cache. And also we have to add a per superblock nfs_sync_lock to cover the lock for alloc inode and that for inode in question. this is because ocfs2_get_dentry() and ocfs2_delete_inode() lock on them in reverse order. nfs_sync_lock is locked in EX mode in ocfs2_get_dentry() and in PR mode in ocfs2_delete_inode(). so that mutliple ocfs2_delete_inode() can run concurrently in normal case. [mfasheh@suse.com: build warning fixes and comment cleanups] Signed-off-by: Wengang Wang Acked-by: Joel Becker Signed-off-by: Mark Fasheh --- fs/ocfs2/suballoc.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/ocfs2/suballoc.h') diff --git a/fs/ocfs2/suballoc.h b/fs/ocfs2/suballoc.h index ea85a4c8b4b1..8c9a78a43164 100644 --- a/fs/ocfs2/suballoc.h +++ b/fs/ocfs2/suballoc.h @@ -188,4 +188,6 @@ int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et, u32 clusters_to_add, u32 extents_to_split, struct ocfs2_alloc_context **data_ac, struct ocfs2_alloc_context **meta_ac); + +int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res); #endif /* _CHAINALLOC_H_ */ -- cgit v1.2.2