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4d11a40239
When we log changes to the superblock, we first have to write them to the on-disk buffer, and then log that. Right now we have a complex bitfield based arrangement to only write the modified field to the buffer before we log it. This used to be necessary as a performance optimisation because we logged the superblock buffer in every extent or inode allocation or freeing, and so performance was extremely important. We haven't done this for years, however, ever since the lazy superblock counters pulled the superblock logging out of the transaction commit fast path. Hence we have a bunch of complexity that is not necessary that makes writing the in-core superblock to disk much more complex than it needs to be. We only need to log the superblock now during management operations (e.g. during mount, unmount or quota control operations) so it is not a performance critical path anymore. As such, remove the complex field based logging mechanism and replace it with a simple conversion function similar to what we use for all other on-disk structures. This means we always log the entirity of the superblock, but again because we rarely modify the superblock this is not an issue for log bandwidth or CPU time. Indeed, if we do log the superblock frequently, delayed logging will minimise the impact of this overhead. [Fixed gquota/pquota inode sharing regression noticed by bfoster.] Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com> |
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| .. | ||
| xfs_alloc_btree.c | ||
| xfs_alloc_btree.h | ||
| xfs_alloc.c | ||
| xfs_alloc.h | ||
| xfs_attr_leaf.c | ||
| xfs_attr_leaf.h | ||
| xfs_attr_remote.c | ||
| xfs_attr_remote.h | ||
| xfs_attr_sf.h | ||
| xfs_attr.c | ||
| xfs_bit.h | ||
| xfs_bmap_btree.c | ||
| xfs_bmap_btree.h | ||
| xfs_bmap.c | ||
| xfs_bmap.h | ||
| xfs_btree.c | ||
| xfs_btree.h | ||
| xfs_cksum.h | ||
| xfs_da_btree.c | ||
| xfs_da_btree.h | ||
| xfs_da_format.c | ||
| xfs_da_format.h | ||
| xfs_dir2_block.c | ||
| xfs_dir2_data.c | ||
| xfs_dir2_leaf.c | ||
| xfs_dir2_node.c | ||
| xfs_dir2_priv.h | ||
| xfs_dir2_sf.c | ||
| xfs_dir2.c | ||
| xfs_dir2.h | ||
| xfs_dquot_buf.c | ||
| xfs_format.h | ||
| xfs_ialloc_btree.c | ||
| xfs_ialloc_btree.h | ||
| xfs_ialloc.c | ||
| xfs_ialloc.h | ||
| xfs_inode_buf.c | ||
| xfs_inode_buf.h | ||
| xfs_inode_fork.c | ||
| xfs_inode_fork.h | ||
| xfs_log_format.h | ||
| xfs_log_recover.h | ||
| xfs_log_rlimit.c | ||
| xfs_quota_defs.h | ||
| xfs_rtbitmap.c | ||
| xfs_sb.c | ||
| xfs_sb.h | ||
| xfs_shared.h | ||
| xfs_symlink_remote.c | ||
| xfs_trans_resv.c | ||
| xfs_trans_resv.h | ||
| xfs_trans_space.h | ||