From dd4759255188771e60cf3455982959a1ba04f4eb Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 25 Nov 2014 11:51:23 -0500 Subject: ext4: limit number of scanned extents in status tree shrinker Currently we scan extent status trees of inodes until we reclaim nr_to_scan extents. This can however require a lot of scanning when there are lots of delayed extents (as those cannot be reclaimed). Change shrinker to work as shrinkers are supposed to and *scan* only nr_to_scan extents regardless of how many extents did we actually reclaim. We however need to be careful and avoid scanning each status tree from the beginning - that could lead to a situation where we would not be able to reclaim anything at all when first nr_to_scan extents in the tree are always unreclaimable. We remember with each inode offset where we stopped scanning and continue from there when we next come across the inode. Note that we also need to update places calling __es_shrink() manually to pass reasonable nr_to_scan to have a chance of reclaiming anything and not just 1. Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o --- fs/ext4/super.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index e2a17f8..4831849 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -874,6 +874,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) INIT_LIST_HEAD(&ei->i_es_list); ei->i_es_all_nr = 0; ei->i_es_shk_nr = 0; + ei->i_es_shrink_lblk = 0; ei->i_reserved_data_blocks = 0; ei->i_reserved_meta_blocks = 0; ei->i_allocated_meta_blocks = 0; -- cgit v1.1