changes in arc_reclaim_needed

[Andriy Gapon]

Pawel,

I would like to go ahead and commit a (much tested now) change to arc_reclaim_needed:

Index: sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
===================================================================
--- sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	(revision 212636)
+++ sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	(working copy)
@@ -2164,7 +2164,7 @@
 	 * If pages are needed or we're within 2048 pages
 	 * of needing to page need to reclaim
 	 */
-	if (vm_pages_needed || (vm_paging_target() > -2048))
+	if (vm_paging_needed())
 		return (1);

 #if 0

Additionally I also want to commit the following change:
Index: sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
===================================================================
--- sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	(revision 212636)
+++ sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	(working copy)
@@ -2155,10 +2155,6 @@
 #ifdef _KERNEL
 	if (needfree)
 		return (1);
-	if (arc_size > arc_c_max)
-		return (1);
-	if (arc_size <= arc_c_min)
-		return (0);

 	/*
 	 * If pages are needed or we're within 2048 pages

Rationale.
OpenSolaris upstream code doesn't have these checks.
I've been using code changed as above for more than two months and all this time
ARC size always stayed within its bounds.
So the range is enforced in some other, more appropriate places.

Reducing diff with upstream is also not bad.

-- 
Andriy Gapon