svn commit: r314857 - stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Andriy Gapon]

Author: avg
Date: Tue Mar  7 15:27:23 2017
New Revision: 314857
URL: https://svnweb.freebsd.org/changeset/base/314857

Log:
  MFC r314058: zfs: lower priority of zio_write_issue threads by four
  
  Obtained from:	Panzura
  Sponsored by:	Panzura

Modified:
  stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c
==============================================================================
--- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c	Tue Mar  7 14:01:33 2017	(r314856)
+++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c	Tue Mar  7 15:27:23 2017	(r314857)
@@ -924,9 +924,17 @@ spa_taskqs_init(spa_t *spa, zio_type_t t
 			 * The write issue taskq can be extremely CPU
 			 * intensive.  Run it at slightly lower priority
 			 * than the other taskqs.
+			 * FreeBSD notes:
+			 * - numerically higher priorities are lower priorities;
+			 * - if priorities divided by four (RQ_PPQ) are equal
+			 *   then a difference between them is insignificant.
 			 */
 			if (t == ZIO_TYPE_WRITE && q == ZIO_TASKQ_ISSUE)
-				pri++;
+#ifdef illumos
+				pri--;
+#else
+				pri += 4;
+#endif
 
 			tq = taskq_create_proc(name, value, pri, 50,
 			    INT_MAX, spa->spa_proc, flags);