svn commit: r197623 - stable/8

[Ken Smith]

Author: kensmith
Date: Tue Sep 29 19:57:06 2009
New Revision: 197623
URL: http://svn.freebsd.org/changeset/base/197623

Log:
  Update description of debugging support.
  
  Submitted by:	ivoras (but heavily modified)
  Pointy hat:	me
  Approved by:	re (implicit)

Modified:
  stable/8/UPDATING

Modified: stable/8/UPDATING
==============================================================================
--- stable/8/UPDATING	Tue Sep 29 19:50:50 2009	(r197622)
+++ stable/8/UPDATING	Tue Sep 29 19:57:06 2009	(r197623)
@@ -8,19 +8,12 @@ Items affecting the ports and packages s
 /usr/ports/UPDATING.  Please read that file before running
 portupgrade.
 
-NOTE TO PEOPLE WHO THINK THAT FreeBSD 8.x IS SLOW:
-	FreeBSD 8.x has many debugging features turned on, in
-	both the kernel and userland.  These features attempt to detect
-	incorrect use of system primitives, and encourage loud failure
-	through extra sanity checking and fail stop semantics.  They
-	also substantially impact system performance.  If you want to
-	do performance measurement, benchmarking, and optimization,
-	you'll want to turn them off.  This includes various WITNESS-
-	related kernel options, INVARIANTS, malloc debugging flags
-	in userland, and various verbose features in the kernel.  Many
-	developers choose to disable these features on build machines
-	to maximize performance.  (To disable malloc debugging, run
-	ln -s aj /etc/malloc.conf.)
+NOTE TO PEOPLE WHO THINK THAT FreeBSD 8.x IS SLOW ON IA64 OR SUN4V:
+	For ia64 the INVARIANTS and INVARIANTS_SUPPORT kernel options
+	were left in the GENERIC kernel because the kernel does not
+	work properly without them.  For sun4v all of the normal kernel
+	debugging tools present in HEAD were left in place because
+	sun4v support still needs work to become production ready.
 
 20090929:
 	802.11s D3.03 support was committed. This is incompatible with