Author: mav Date: Sun Jan 25 14:31:44 2015 New Revision: 277701 URL: https://svnweb.freebsd.org/changeset/base/277701
Log: MFC r276983: When aggregating TRIM segments, move the new one to the end. New segment at the list head may block all TRIM requests until txg of that segment can be processed. On my random I/O tests this change reduce peak TRIM list length from 650 to 450 segments. Hopefully it should reduce TRIM burstiness when list processing is unblocked. Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/trim_map.c Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/trim_map.c ============================================================================== --- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/trim_map.c Sun Jan 25 14:29:40 2015 (r277700) +++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/trim_map.c Sun Jan 25 14:31:44 2015 (r277701) @@ -253,17 +253,23 @@ trim_map_segment_add(trim_map_t *tm, uin ts_after->ts_start = ts_before->ts_start; ts_after->ts_txg = txg; ts_after->ts_time = time; + list_remove(&tm->tm_head, ts_after); + list_insert_tail(&tm->tm_head, ts_after); kmem_free(ts_before, sizeof (*ts_before)); } else if (merge_before) { TRIM_MAP_SINC(tm, end - ts_before->ts_end); ts_before->ts_end = end; ts_before->ts_txg = txg; ts_before->ts_time = time; + list_remove(&tm->tm_head, ts_before); + list_insert_tail(&tm->tm_head, ts_before); } else if (merge_after) { TRIM_MAP_SINC(tm, ts_after->ts_start - start); ts_after->ts_start = start; ts_after->ts_txg = txg; ts_after->ts_time = time; + list_remove(&tm->tm_head, ts_after); + list_insert_tail(&tm->tm_head, ts_after); } else { TRIM_MAP_SINC(tm, end - start); TRIM_MAP_QINC(tm); _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"