[src/netbsd-1-6]: src/sys/arch/sparc/sparc Pullup via patch (requested by pk ...

[jmc <jmc%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/9f5b385d6386
branches:  netbsd-1-6
changeset: 530962:9f5b385d6386
user:      jmc <jmc%NetBSD.org@localhost>
date:      Wed Oct 22 06:22:20 2003 +0000

description:
Pullup via patch (requested by pk in ticket #1535)
On small sun4c machines trim the buffer cache to reduce the demand for
 kernel virtual memory. This leaves more of the precious PMEG resources
 available for user space VM which speeds up things considerably, since
 a reasonable PMEG working set can be maintained.

diffstat:

 sys/arch/sparc/sparc/machdep.c |  15 ++++++++++++++-
 1 files changed, 14 insertions(+), 1 deletions(-)

diffs (29 lines):

diff -r 1d7d83fa7716 -r 9f5b385d6386 sys/arch/sparc/sparc/machdep.c
--- a/sys/arch/sparc/sparc/machdep.c    Wed Oct 22 06:19:14 2003 +0000
+++ b/sys/arch/sparc/sparc/machdep.c    Wed Oct 22 06:22:20 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: machdep.c,v 1.193 2002/03/28 15:45:01 pk Exp $ */
+/*     $NetBSD: machdep.c,v 1.193.4.1 2003/10/22 06:22:20 jmc Exp $ */
 
 /*-
  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
@@ -272,6 +272,19 @@
        printf("total memory = %s\n", pbuf);
 
        /*
+        * Tune buffer cache variables based on the capabilities of the MMU
+        * to cut down on VM space allocated for the buffer caches that    
+        * would lead to MMU resource shortage.
+        */
+       if (CPU_ISSUN4C) {
+               /* Clip UBC windows */
+               if (cpuinfo.mmu_nsegment <= 128) {
+                       ubc_nwins = 256; 
+                       /*ubc_winshift = 12; tune this too? */
+               }       
+       }       
+
+       /*      
         * Find out how much space we need, allocate it,
         * and then give everything true virtual addresses.
         */