[src/trunk]: src/sys/arch/amd64/include bump PAGER_MAP_DEFAULT_SIZE to 512MB....

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

details:   https://anonhg.NetBSD.org/src/rev/cf5b00a5c6c5
branches:  trunk
changeset: 827758:cf5b00a5c6c5
user:      mrg <mrg%NetBSD.org@localhost>
date:      Sat Nov 11 20:23:49 2017 +0000

description:
bump PAGER_MAP_DEFAULT_SIZE to 512MB.  this should allow more
concurrent IOs to be possible, and i'm unable to see pager_map
contention any more.

other larger platforms should probably do this too.

ok chs@.

diffstat:

 sys/arch/amd64/include/vmparam.h |  8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diffs (22 lines):

diff -r 59e6da74576a -r cf5b00a5c6c5 sys/arch/amd64/include/vmparam.h
--- a/sys/arch/amd64/include/vmparam.h  Sat Nov 11 19:25:29 2017 +0000
+++ b/sys/arch/amd64/include/vmparam.h  Sat Nov 11 20:23:49 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vmparam.h,v 1.43 2017/06/24 13:43:36 joerg Exp $       */
+/*     $NetBSD: vmparam.h,v 1.44 2017/11/11 20:23:49 mrg Exp $ */
 
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
@@ -57,6 +57,12 @@
 #define        PAGE_MASK       (PAGE_SIZE - 1)
 
 /*
+ * Default pager_map of 16MB is awfully small.  There is have plenty
+ * of VA so use it.
+ */
+#define        PAGER_MAP_DEFAULT_SIZE (512 * 1024 * 1024)
+
+/*
  * USRSTACK is the top (end) of the user stack. Immediately above the
  * user stack resides the user structure, which is UPAGES long and contains
  * the kernel stack.