From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tao Ma Subject: [PATCH 4/4 v2] ext4: Speed up FITRIM by recording flags in ext4_group_info. Date: Thu, 10 Feb 2011 15:33:26 +0800 Message-ID: <1297323206-9874-1-git-send-email-tm@tao.ma> References: <1297231048-3458-4-git-send-email-tm@tao.ma> Cc: Andreas Dilger , Lukas Czerner To: linux-ext4@vger.kernel.org Return-path: Received: from cpoproxy3-pub.bluehost.com ([67.222.54.6]:48251 "HELO cpoproxy3-pub.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750897Ab1BJHe7 (ORCPT ); Thu, 10 Feb 2011 02:34:59 -0500 In-Reply-To: <1297231048-3458-4-git-send-email-tm@tao.ma> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Tao Ma 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. After I delete some big image files and re-run the trim, 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: Andreas Dilger Cc: Lukas Czerner Signed-off-by: Tao Ma --- fs/ext4/ext4.h | 8 +++++++- fs/ext4/mballoc.c | 22 ++++++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0c8d97b..1d59a63 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. */ + u64 s_last_trim_minblks; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) @@ -1970,10 +1973,13 @@ 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_HAS_BEEN_TRIMMED(grp) \ + (test_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..c7aa094 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2687,6 +2687,16 @@ 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)) + clear_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, + &(db->bb_state)); + 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 +4782,10 @@ ext4_grpblk_t ext4_trim_all_free(struct super_block *sb, struct ext4_buddy *e4b, ext4_lock_group(sb, group); + if (EXT4_MB_GRP_HAS_BEEN_TRIMMED(e4b->bd_info) && + minblocks >= EXT4_SB(sb)->s_last_trim_minblks) + goto out; + trace_ext4_trim_all_free(sb, group, start, max); while (start < max) { @@ -4804,6 +4818,11 @@ 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) + set_bit(EXT4_GROUP_INFO_WAS_TRIMMED_BIT, + &(e4b->bd_info->bb_state)); +out: ext4_unlock_group(sb, group); ext4_debug("trimmed %d blocks in the group %d\n", @@ -4892,6 +4911,9 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) } range->len = trimmed * sb->s_blocksize; + if (!ret) + EXT4_SB(sb)->s_last_trim_minblks = minlen; + out: return ret; } -- 1.6.3.GIT