From: Jan Kara Date: Tue, 9 Apr 2013 16:39:26 +0000 (-0400) Subject: ext4: improve credit estimate for EXT4_SINGLEDATA_TRANS_BLOCKS X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=f45a5ef91bef7e02149a216ed6dc3fcdd8b38268;p=deliverable%2Flinux.git ext4: improve credit estimate for EXT4_SINGLEDATA_TRANS_BLOCKS Estimate of 27 credits for allocation of a block in extent based inode is unnecessarily high. We can easily argue 20 is enough. Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o" --- diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h index aeed0bac693b..c8c6885406db 100644 --- a/fs/ext4/ext4_jbd2.h +++ b/fs/ext4/ext4_jbd2.h @@ -29,11 +29,13 @@ * block to complete the transaction. * * For extents-enabled fs we may have to allocate and modify up to - * 5 levels of tree + root which are stored in the inode. */ + * 5 levels of tree, data block (for each of these we need bitmap + group + * summaries), root which is stored in the inode, sb + */ #define EXT4_SINGLEDATA_TRANS_BLOCKS(sb) \ (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS) \ - ? 27U : 8U) + ? 20U : 8U) /* Extended attribute operations touch at most two data buffers, * two bitmap buffers, and two group summaries, in addition to the inode