Change Details

This patch implements parallel algotrithm for mounting zfs filesystems. This feature was first implemented on Illumos and ported to ZOL. After asking on the zfs-devel mailing list it was suggested that I start with the ZOL patch. Mail thread here: https://lists.freebsd.org/pipermail/zfs-devel/2019-February/000516.html Porting Notes: * the ZOL patch pretty much applies directly to FreeBSD (unlike the Illumos patch) * Had to take some code from the Illumos patch for `#ifdef Illumos` specific code that was removed when ported to ZOL * After the ZOL port, a fix for a race condition was amended, this is included. (https://github.com/zfsonlinux/zfs/commit/e63ac16d25fbe991a356489c86d4077567dfea21) ZOL-commit: https://github.com/zfsonlinux/zfs/commit/a10d50f999511d304f910852c7825c70c9c9e303

This patch implements parallel mounting for zfs filesystems. This was first implemented on Illumos and ported to ZOL. After asking on the zfs-devel mailing list it was suggested that I start with the ZOL patch because it would be easier to port. Delphix has seen huge decrease in latency of the mount phase with this patch (see results here: https://github.com/openzfs/openzfs/commit/a3f0e2b569). Performance improvements measured at Gandi are on par with those at Delphix. Mailing thread here: https://lists.freebsd.org/pipermail/zfs-devel/2019-February/000516.html Porting Notes: * the ZOL patch pretty much applies directly to FreeBSD (unlike the Illumos patch) * Had to take some code from the Illumos patch for `#ifdef Illumos` specific code that was removed when ported to ZOL * After the ZOL port, a fix for a race condition was amended, this is included. (https://github.com/zfsonlinux/zfs/commit/e63ac16d25fbe991a356489c86d4077567dfea21) ZOL-commit: https://github.com/zfsonlinux/zfs/commit/a10d50f999511d304f910852c7825c70c9c9e303

This patch implements parallel algotrithmmounting for mounting zfs filesystems. This feature was first implemented on Illumos and ported to ZOL. After asking on the zfs-devel mailing list it was suggested that I start with the ZOL patch because it would be easier to port. MailDelphix has seen huge decrease in latency of the mount phase with this patch (see results here: https://github.com/openzfs/openzfs/commit/a3f0e2b569). Performance improvements measured at Gandi are on par with those at Delphix. Mailing thread here: https://lists.freebsd.org/pipermail/zfs-devel/2019-February/000516.html Porting Notes: * the ZOL patch pretty much applies directly to FreeBSD (unlike the Illumos patch) * Had to take some code from the Illumos patch for `#ifdef Illumos` specific code that was removed when ported to ZOL * After the ZOL port, a fix for a race condition was amended, this is included. (https://github.com/zfsonlinux/zfs/commit/e63ac16d25fbe991a356489c86d4077567dfea21) ZOL-commit: https://github.com/zfsonlinux/zfs/commit/a10d50f999511d304f910852c7825c70c9c9e303