Implement BUFCACHEPERCENT. Allow bufpages/nbuf larger than 1 (still max out

at all buffers be MAXBSIZE).  Remove faulty limit test of buffer pages
allocation.  The check is now done at the bufpages+nbuf calculations.

diff --git a/sys/arch/arc/arc/machdep.c b/sys/arch/arc/arc/machdep.c
index 755fd0f..36aba12 100644 (file)
--- a/sys/arch/arc/arc/machdep.c
+++ b/sys/arch/arc/arc/machdep.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: machdep.c,v 1.17 1997/01/28 03:54:52 deraadt Exp $    */
+/*     $OpenBSD: machdep.c,v 1.18 1997/02/01 11:02:41 deraadt Exp $    */
 /*
  * Copyright (c) 1988 University of Utah.
  * Copyright (c) 1992, 1993
@@ -38,7 +38,7 @@
  * SUCH DAMAGE.
  *
  *     from: @(#)machdep.c     8.3 (Berkeley) 1/12/94
- *      $Id: machdep.c,v 1.17 1997/01/28 03:54:52 deraadt Exp $
+ *      $Id: machdep.c,v 1.18 1997/02/01 11:02:41 deraadt Exp $
  */
 
 /* from: Utah Hdr: machdep.c 1.63 91/04/24 */
@@ -406,6 +406,10 @@ mips_init(argc, argv, code)
        valloc(msqids, struct msqid_ds, msginfo.msgmni);
 #endif
 
+#ifndef BUFCACHEPERCENT
+#define BUFCACHEPERCENT 5
+#endif
+
        /*
         * Determine how many buffers to allocate.
         * We allocate more buffer space than the BSD standard of
@@ -413,13 +417,29 @@ mips_init(argc, argv, code)
         * We just allocate a flat 10%. Ensure a minimum of 16 buffers.
         * We allocate 1/2 as many swap buffer headers as file i/o buffers.
         */
-       if (bufpages == 0)
-               bufpages = physmem / 10 / CLSIZE;
+       if (bufpages == 0) {
+               if (physmem < btoc(2 * 1024 * 1024))
+                       bufpages = physmem / (10 * CLSIZE);
+               else
+                       bufpages = (btoc(2 * 1024 * 1024) + physmem) /
+                           ((100/BUFCACHEPERCENT) * CLSIZE);
+       }
        if (nbuf == 0) {
                nbuf = bufpages;
                if (nbuf < 16)
                        nbuf = 16;
        }
+
+       /* Restrict to at most 70% filled kvm */
+       if (nbuf * MAXBSIZE >
+           (VM_MAX_KERNEL_ADDRESS-VM_MIN_KERNEL_ADDRESS) * 7 / 10)
+               nbuf = (VM_MAX_KERNEL_ADDRESS-VM_MIN_KERNEL_ADDRESS) /
+                   MAXBSIZE * 7 / 10;
+
+       /* More buffer pages than fits into the buffers is senseless.  */
+       if (bufpages > nbuf * MAXBSIZE / CLBYTES)
+               bufpages = nbuf * MAXBSIZE / CLBYTES;
+
        if (nswbuf == 0) {
                nswbuf = (nbuf / 2) &~ 1;       /* force even */
                if (nswbuf > 256)
@@ -561,6 +581,12 @@ cpu_startup()
                panic("startup: cannot allocate buffers");
        base = bufpages / nbuf;
        residual = bufpages % nbuf;
+       if (base >= MAXBSIZE / CLBYTES) {
+               /* don't want to alloc more physical mem than needed */
+               base = MAXBSIZE / CLBYTES;
+               residual = 0;
+       }
+
        for (i = 0; i < nbuf; i++) {
                vm_size_t curbufsize;
                vm_offset_t curbuf;