Author: [EMAIL PROTECTED]
Date: Fri Dec 5 09:37:12 2008
New Revision: 926
Modified:
branches/bleeding_edge/src/zone.cc
branches/bleeding_edge/src/zone.h
Log:
Partial fix for issue 173:
- Do not keep growing the zone segment size exponentially. By putting
an upper limit on the segment size we limit the requirements for
contiguous memory allocation.
Review URL: http://codereview.chromium.org/12984
Modified: branches/bleeding_edge/src/zone.cc
==============================================================================
--- branches/bleeding_edge/src/zone.cc (original)
+++ branches/bleeding_edge/src/zone.cc Fri Dec 5 09:37:12 2008
@@ -163,8 +163,23 @@
// is to avoid excessive malloc() and free() overhead.
Segment* head = Segment::head();
int old_size = (head == NULL) ? 0 : head->size();
- int new_size = sizeof(Segment) + kAlignment + size + (old_size << 1);
- if (new_size < kMinimumSegmentSize) new_size = kMinimumSegmentSize;
+ static const int kSegmentOverhead = sizeof(Segment) + kAlignment;
+ int new_size = kSegmentOverhead + size + (old_size << 1);
+ if (new_size < kMinimumSegmentSize) {
+ new_size = kMinimumSegmentSize;
+ } else if (new_size > kMaximumSegmentSize) {
+ // Limit the size of new segments to avoid growing the segment size
+ // exponentially, thus putting pressure on contiguous virtual address
+ // space.
+ if (size > (kMaximumSegmentSize - kSegmentOverhead)) {
+ // Make sure to allocate a segment at large enough to hold the
requested
+ // size.
+ new_size = kSegmentOverhead + size;
+ } else {
+ // Allocate a new segment of maximum size.
+ new_size = kMaximumSegmentSize;
+ }
+ }
Segment* segment = Segment::New(new_size);
if (segment == NULL) V8::FatalProcessOutOfMemory("Zone");
Modified: branches/bleeding_edge/src/zone.h
==============================================================================
--- branches/bleeding_edge/src/zone.h (original)
+++ branches/bleeding_edge/src/zone.h Fri Dec 5 09:37:12 2008
@@ -74,6 +74,9 @@
// Never allocate segments smaller than this size in bytes.
static const int kMinimumSegmentSize = 8 * KB;
+
+ // Never allocate segments larger than this size in bytes.
+ static const int kMaximumSegmentSize = 1 * MB;
// Never keep segments larger than this size in bytes around.
static const int kMaximumKeptSegmentSize = 64 * KB;
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