runtime: fallback to 128M address space on 32bit

Available darwin/arm devices sporadically have trouble mapping 256M.

I would really appreciate it if anyone could check my working on
this, and make sure sure there aren't obviously bad consequences I
haven't considered.

Change-Id: Id1a8edae104d974fcf5f9333274f958625467f79
Reviewed-on: https://go-review.googlesource.com/5752
Reviewed-by: Keith Randall <khr@golang.org>

diff --git a/src/runtime/malloc.go b/src/runtime/malloc.go
index fac5ca49ce3202bb383737fd66ca3d0265ef0122..6a2c85aa9f6d15f5d82cf8f79321466c794d1e00 100644 (file)
--- a/src/runtime/malloc.go
+++ b/src/runtime/malloc.go
@@ -292,6 +292,7 @@ func mallocinit() {
                arenaSizes := []uintptr{
                        512 << 20,
                        256 << 20,
+                       128 << 20,
                }
 
                for _, arenaSize := range arenaSizes {