Remove eager sweeping for lazy swept spaces. Try to find in SlowAllocateRaw a bounded number of tim…

Remove eager sweeping for lazy swept spaces. Try to find in SlowAllocateRaw a bounded number of times a big enough memory slot.


BUG=v8:2194
Committed: https://code.google.com/p/v8/source/detail?r=13058

[Michael Starzinger, 2012-11-26 13:35:44]

This is looking good. I will compile it into Chromium to smoke-test it.

https://codereview.chromium.org/11420036/diff/1/src/spaces.cc
File src/spaces.cc (right):

https://codereview.chromium.org/11420036/diff/1/src/spaces.cc#newcode2397
src/spaces.cc:2397: int i = 0;
Move the declaration of "i" into to for statement.

https://codereview.chromium.org/11420036/diff/1/src/spaces.cc#newcode2399
src/spaces.cc:2399: for (i = 0; i < kMaxSweepingTries &&
first_unswept_page_->is_valid(); i++) {
We shouldn't check against first_unswept_page_ directly because with parallel
sweeping these accesses need to be synchronized. Better just use the boolean
value that AdvanceSweeper returns to determine whether to continue or not. Like
this ...

const int kMaxSweepingTries = 5;
bool sweeping_complete = false;

for (int i = 0; i < kMaxSweepingTries && !sweeping_complete; i++) {
  sweeping_complete = AdvanceSweeper(size_in_bytes);
  [...]
}

[Hannes Payer (out of office), 2012-11-26 14:06:40]

https://codereview.chromium.org/11420036/diff/1/src/spaces.cc
File src/spaces.cc (right):

https://codereview.chromium.org/11420036/diff/1/src/spaces.cc#newcode2397
src/spaces.cc:2397: int i = 0;
On 2012/11/26 13:35:44, Michael Starzinger wrote:
> Move the declaration of "i" into to for statement.

Done.

https://codereview.chromium.org/11420036/diff/1/src/spaces.cc#newcode2399
src/spaces.cc:2399: for (i = 0; i < kMaxSweepingTries &&
first_unswept_page_->is_valid(); i++) {
On 2012/11/26 13:35:44, Michael Starzinger wrote:
> We shouldn't check against first_unswept_page_ directly because with parallel
> sweeping these accesses need to be synchronized. Better just use the boolean
> value that AdvanceSweeper returns to determine whether to continue or not.
Like
> this ...
> 
> const int kMaxSweepingTries = 5;
> bool sweeping_complete = false;
> 
> for (int i = 0; i < kMaxSweepingTries && !sweeping_complete; i++) {
>   sweeping_complete = AdvanceSweeper(size_in_bytes);
>   [...]
> }

Done.

[Michael Starzinger, 2012-11-26 14:31:08]

LGTM.