Make heap size estimation more accurate.

Make heap size estimation more accurate.

This improves the heap size estimation by not counting lazy swept pages
as completely allocated but use their live bytes counter instead.

R=vegorov@chromium.org
BUG=v8:1893
TEST=cctest/test-heap/TestSizeOfObjects

Committed: http://code.google.com/p/v8/source/detail?r=10383

[Vyacheslav Egorov (Chromium), 2012-01-10 17:42:43]

http://codereview.chromium.org/9173001/diff/3001/src/spaces.cc
File src/spaces.cc (right):

http://codereview.chromium.org/9173001/diff/3001/src/spaces.cc#newcode752
src/spaces.cc:752: intptr_t PagedSpace::SizeOfObjectsSlow() {
we will call this function at least once at the end of GC (see garbage
collection epilogue).

I wonder if you can compute sum of "delayed" live bytes while in
MarkCompactCollector::SweepSpace and then adjust it while lazy sweeping
progresses.

[Michael Starzinger, 2012-01-11 09:55:57]

PTAL.

http://codereview.chromium.org/9173001/diff/3001/src/spaces.cc
File src/spaces.cc (right):

http://codereview.chromium.org/9173001/diff/3001/src/spaces.cc#newcode752
src/spaces.cc:752: intptr_t PagedSpace::SizeOfObjectsSlow() {
On 2012/01/10 17:42:43, Vyacheslav Egorov wrote:
> we will call this function at least once at the end of GC (see garbage
> collection epilogue).
> 
> I wonder if you can compute sum of "delayed" live bytes while in
> MarkCompactCollector::SweepSpace and then adjust it while lazy sweeping
> progresses.

Done. Yes, we can.

[Vyacheslav Egorov (Chromium), 2012-01-11 10:16:49]

LGTM!

http://codereview.chromium.org/9173001/diff/11001/src/mark-compact.cc
File src/mark-compact.cc (right):

http://codereview.chromium.org/9173001/diff/11001/src/mark-compact.cc#newcode...
src/mark-compact.cc:3644: space->MarkPageForLazySweep(p);
I would call it MarkPageForLazySweeping

http://codereview.chromium.org/9173001/diff/11001/src/spaces.h
File src/spaces.h (right):

http://codereview.chromium.org/9173001/diff/11001/src/spaces.h#newcode1663
src/spaces.h:1663: intptr_t unswept_dead_bytes_;
I would call them free not dead (I think object can be dead but not the byte).

[Michael Starzinger, 2012-01-11 10:34:00]

Added new patch set. Landed.

http://codereview.chromium.org/9173001/diff/11001/src/mark-compact.cc
File src/mark-compact.cc (right):

http://codereview.chromium.org/9173001/diff/11001/src/mark-compact.cc#newcode...
src/mark-compact.cc:3644: space->MarkPageForLazySweep(p);
On 2012/01/11 10:16:49, Vyacheslav Egorov wrote:
> I would call it MarkPageForLazySweeping

Done.

http://codereview.chromium.org/9173001/diff/11001/src/spaces.h
File src/spaces.h (right):

http://codereview.chromium.org/9173001/diff/11001/src/spaces.h#newcode1663
src/spaces.h:1663: intptr_t unswept_dead_bytes_;
On 2012/01/11 10:16:49, Vyacheslav Egorov wrote:
> I would call them free not dead (I think object can be dead but not the byte).

Done.