freebsd-nq/sys/cddl
Alexander Motin 2de874ed23 Add LBA as secondary sort key for synchronous I/O requests.
On FreeBSD gethrtime() implemented via getnanouptime(), that has 1ms (1/hz)
precision.  It makes primary sort key (timestamp) collision very possible.
In such situations sorting by secondary key of LBA is much more reasonable
then by totally meaningless zio pointer value.

With this change on multi-threaded synchronous ZVOL read I've measured 10%
throughput increase and average latency reduction.

MFC after:	2 weeks
2015-01-11 00:26:18 +00:00
..
boot/zfs MFV r274273: 2014-11-10 08:20:21 +00:00
compat/opensolaris remove opensolaris cyclic code, replace with high-precision callouts 2014-12-07 11:21:41 +00:00
contrib/opensolaris Add LBA as secondary sort key for synchronous I/O requests. 2015-01-11 00:26:18 +00:00
dev Restore the trap type argument to the DTrace trap hook, removed in r268600. 2014-12-23 15:38:19 +00:00