writeback: move inodes from one super_block together
__mark_inode_dirty adds inode to wb dirty list in random order. If a disk has several partitions, writeback might keep spindle moving between partitions. To reduce the move, better write big chunk of one partition and then move to another. Inodes from one fs usually are in one partion, so idealy move indoes from one fs together should reduce spindle move. This patch tries to address this. Before per-bdi writeback is added, the behavior is write indoes from one fs first and then another, so the patch restores previous behavior. The loop in the patch is a bit ugly, should we add a dirty list for each superblock in bdi_writeback? Test in a two partition disk with attached fio script shows about 3% ~ 6% improvement. Signed-off-by: NShaohua Li <shaohua.li@intel.com> Reviewed-by: NWu Fengguang <fengguang.wu@intel.com> Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
Showing
想要评论请 注册 或 登录