From: Tao Ma Subject: [PATCH 4/4 V3] ext4: Speed up FITRIM by recording flags in ext4_group_info. Date: Thu, 24 Feb 2011 22:18:48 +0800 Message-ID: <1298557128-4548-1-git-send-email-tm@tao.ma> References: Cc: lczerner@redhat.com To: linux-ext4@vger.kernel.org Return-path: Received: from cpoproxy1-pub.bluehost.com ([69.89.21.11]:49009 "HELO cpoproxy1-pub.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754868Ab1BXOTG (ORCPT ); Thu, 24 Feb 2011 09:19:06 -0500 In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: changlog from v2 -> v3: change s_last_trim_minblks from u64 to atomic_t to avoid a race. Regards, Tao >From 3875493dea3cc25be5460c175267f08a7ed540bc Mon Sep 17 00:00:00 2001 From: Tao Ma Date: Fri, 25 Feb 2011 06:10:26 +0800 Subject: [PATCH 4/4 V3] ext4: Speed up FITRIM by recording flags in ext4_group_info. In ext4, when FITRIM is called every time, we iterate all the groups and do trim one by one. It is a bit time wasting if the group has been trimmed and there is no change since the last trim. So this patch adds a new flag in ext4_group_info->bb_state to indicate that the group has been trimmed, and it will be cleared if some blocks is freed(in release_blocks_on_commit). Another trim_minlen is added in ext4_sb_info to record the last minlen we use to trim the volume, so that if the caller provide a small one, we will go on the trim regardless of the bb_state. A simple test with my intel x25m ssd: df -h shows: /dev/sdb2 108G 35G 68G 34% /mnt/ext4 Block size: 4096 run the FITRIM with the following parameter: range.start = 0; range.len = UINT64_MAX; range.minlen = 1048576; without the patch: [root@boyu-tm test]# time ./ftrim /mnt/ext4/a real 0m4.039s user 0m0.000s sys 0m1.020s [root@boyu-tm test]# time ./ftrim /mnt/ext4/a real 0m3.577s user 0m0.001s sys 0m1.004s [root@boyu-tm test]# time ./ftrim /mnt/ext4/a real 0m3.380s user 0m0.000s sys 0m0.991s with the patch: [root@boyu-tm test]# time ./ftrim /mnt/ext4/a real 0m3.466s user 0m0.000s sys 0m0.966s [root@boyu-tm test]# time ./ftrim /mnt/ext4/a real 0m0.001s user 0m0.000s sys 0m0.001s [root@boyu-tm test]# time ./ftrim /mnt/ext4/a real 0m0.001s user 0m0.000s sys 0m0.000s A big improvement for the 2nd and 3rd run. Even after I delete some big image files, it is still much faster than iterating the whole disk. /dev/sdb2 108G 25G 78G 24% /mnt/ext4 [root@boyu-tm test]# time ./ftrim /mnt/ext4/a real 0m0.513s user 0m0.000s sys 0m0.069s Cc: Lukas Czerner Reviewed-by: Andreas Dilger Signed-off-by: Tao Ma --- fs/ext4/ext4.h | 13 ++++++++++++- fs/ext4/mballoc.c | 20 ++++++++++++++++++++ fs/ext4/super.c | 2 ++ 3 files changed, 34 insertions(+), 1 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0c8d97b..715c0a4 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1200,6 +1200,9 @@ struct ext4_sb_info { struct ext4_li_request *s_li_request; /* Wait multiplier for lazy initialization thread */ unsigned int s_li_wait_mult; + + /* record the last minlen when FITRIM is called. */ + atomic_t s_last_trim_minblks; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) @@ -1970,11 +1973,19 @@ struct ext4_group_info { * 5 free 8-block regions. */ }; -#define EXT4_GROUP_INFO_NEED_INIT_BIT 0 +#define EXT4_GROUP_INFO_NEED_INIT_BIT 0 +#define EXT4_GROUP_INFO_WAS_TRIMMED_BIT 1 #define EXT4_MB_GRP_NEED_INIT(grp) \ (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state))) +#define EXT4_MB_GRP_WAS_TRIMMED(grp) \ + (test_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state))) +#define EXT4_MB_GRP_SET_TRIMMED(grp) \ + (set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state))) +#define EXT4_MB_GRP_CLEAR_TRIMMED(grp) \ + (clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, &((grp)->bb_state))) + #define EXT4_MAX_CONTENTION 8 #define EXT4_CONTENTION_THRESHOLD 2 diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 4eadac8..29d7d17 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2687,6 +2687,15 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn) rb_erase(&entry->node, &(db->bb_free_root)); mb_free_blocks(NULL, &e4b, entry->start_blk, entry->count); + /* + * Clear the trimmed flag for the group so that the next + * ext4_trim_fs can trim it. + * If the volume is mounted with -o discard, online discard + * is supported and the free blocks will be trimmed online. + */ + if (!test_opt(sb, DISCARD)) + EXT4_MB_GRP_CLEAR_TRIMMED(db); + if (!db->bb_free_root.rb_node) { /* No more items in the per group rb tree * balance refcounts from ext4_mb_free_metadata() @@ -4772,6 +4781,10 @@ ext4_grpblk_t ext4_trim_all_free(struct super_block *sb, struct ext4_buddy *e4b, ext4_lock_group(sb, group); + if (EXT4_MB_GRP_WAS_TRIMMED(e4b->bd_info) && + minblocks >= atomic_read(&EXT4_SB(sb)->s_last_trim_minblks)) + goto out; + trace_ext4_trim_all_free(sb, group, start, max); while (start < max) { @@ -4804,6 +4817,10 @@ ext4_grpblk_t ext4_trim_all_free(struct super_block *sb, struct ext4_buddy *e4b, if ((e4b->bd_info->bb_free - free_count) < minblocks) break; } + + if (!ret) + EXT4_MB_GRP_SET_TRIMMED(e4b->bd_info); +out: ext4_unlock_group(sb, group); ext4_debug("trimmed %d blocks in the group %d\n", @@ -4892,6 +4909,9 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) } range->len = trimmed * sb->s_blocksize; + if (!ret) + atomic_set(&EXT4_SB(sb)->s_last_trim_minblks, minlen); + out: return ret; } diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 4898cb1..0fa3ed6 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3045,6 +3045,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part, sectors[1]); + atomic_set(&sbi->s_last_trim_minblks, 0); + /* Cleanup superblock name */ for (cp = sb->s_id; (cp = strchr(cp, '/'));) *cp = '!'; -- 1.6.3.GIT