svn commit: r289188 - vendor-sys/illumos/dist/uts/common/fs/zfs

[Alexander Motin]

Author: mav
Date: Mon Oct 12 14:27:27 2015
New Revision: 289188
URL: https://svnweb.freebsd.org/changeset/base/289188

Log:
  6281 prefetching should apply to 1MB reads
  
  Reviewed by: Matthew Ahrens <mahrens at delphix.com>
  Reviewed by: Paul Dagnelie <pcd at delphix.com>
  Reviewed by: Alexander Motin <mav at freebsd.org>
  Reviewed by: Dan McDonald <danmcd at omniti.com>
  Reviewed by: Justin Gibbs <gibbs at scsiguy.com>
  Reviewed by: Xin Li <delphij at freebsd.org>
  Approved by: Gordon Ross <gordon.ross at nexenta.com>
  Author: George Wilson <george.wilson at delphix.com>
  
  illumos/illumos-gate at 632802744ef6d17e06d6980a95f631615c3b060f

Modified:
  vendor-sys/illumos/dist/uts/common/fs/zfs/dmu.c
  vendor-sys/illumos/dist/uts/common/fs/zfs/dmu_zfetch.c

Modified: vendor-sys/illumos/dist/uts/common/fs/zfs/dmu.c
==============================================================================
--- vendor-sys/illumos/dist/uts/common/fs/zfs/dmu.c	Mon Oct 12 14:24:11 2015	(r289187)
+++ vendor-sys/illumos/dist/uts/common/fs/zfs/dmu.c	Mon Oct 12 14:27:27 2015	(r289188)
@@ -442,7 +442,7 @@ dmu_buf_hold_array_by_dnode(dnode_t *dn,
 	}
 
 	if ((flags & DMU_READ_NO_PREFETCH) == 0 && read &&
-	    length < zfetch_array_rd_sz) {
+	    length <= zfetch_array_rd_sz) {
 		dmu_zfetch(&dn->dn_zfetch, blkid, nblks);
 	}
 	rw_exit(&dn->dn_struct_rwlock);

Modified: vendor-sys/illumos/dist/uts/common/fs/zfs/dmu_zfetch.c
==============================================================================
--- vendor-sys/illumos/dist/uts/common/fs/zfs/dmu_zfetch.c	Mon Oct 12 14:24:11 2015	(r289187)
+++ vendor-sys/illumos/dist/uts/common/fs/zfs/dmu_zfetch.c	Mon Oct 12 14:27:27 2015	(r289188)
@@ -24,7 +24,7 @@
  */
 
 /*
- * Copyright (c) 2013, 2014 by Delphix. All rights reserved.
+ * Copyright (c) 2013, 2015 by Delphix. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
@@ -49,7 +49,7 @@ uint32_t	zfetch_max_streams = 8;
 uint32_t	zfetch_min_sec_reap = 2;
 /* max bytes to prefetch per stream (default 8MB) */
 uint32_t	zfetch_max_distance = 8 * 1024 * 1024;
-/* number of bytes in a array_read at which we stop prefetching (1MB) */
+/* max number of bytes in an array_read in which we allow prefetching (1MB) */
 uint64_t	zfetch_array_rd_sz = 1024 * 1024;
 
 typedef struct zfetch_stats {