Bug 122352 – [Win] Turn off FastMalloc on Windows

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[Brent Fulgham]

There are a number of test crashes on the Windows platform that seem to be caused by the FastMalloc implementation. As one would expect, these are tied to mismatched new/free pairs, and seem to be related to the visibility of the FastMalloc overloads in template expansions, and perhaps when data is allocated and deallocated across shared library boundaries.

If I force use of the system allocator, these crashes go away.

I cannot measure the performance penalty this might introduce, because we do not currently track Windows performance. However, there does not seem to be a noticeable change in using the MiniBrowser with the system allocator activated. Perhaps I am not using test cases that create/destroy enough memory for this to be noticeable.

I would like to do the following:

1. Turn off FastMalloc on the Windows platform.
2. Reactivate the various tests that currently fail due to issues with the allocator.
3. Get a performance bot running
4. Port ggaren’s new allocator to run on Windows, but only use it if we see no change in stability.

[Brent Fulgham]

Created attachment 213420 [details]
Patch

[Brent Fulgham]

Committed r156933: <http://trac.webkit.org/changeset/156933>

[Radar WebKit Bug Importer]

<rdar://problem/15321791>

[Csaba Osztrogonác]

(In reply to comment #0)
> There are a number of test crashes on the Windows platform that seem to be
> caused by the FastMalloc implementation. As one would expect, these are tied
> to mismatched new/free pairs, and seem to be related to the visibility of
> the FastMalloc overloads in template expansions, and perhaps when data is
> allocated and deallocated across shared library boundaries.
> 
> If I force use of the system allocator, these crashes go away.
> 
> I cannot measure the performance penalty this might introduce, because we do
> not currently track Windows performance. However, there does not seem to be
> a noticeable change in using the MiniBrowser with the system allocator
> activated. Perhaps I am not using test cases that create/destroy enough
> memory for this to be noticeable.
> 
> I would like to do the following:
> 
> 1. Turn off FastMalloc on the Windows platform.
> 2. Reactivate the various tests that currently fail due to issues with the
> allocator.
> 3. Get a performance bot running
> 4. Port ggaren’s new allocator to run on Windows, but only use it if we see
> no change in stability.

Is there any plan to switch the Windows port to bmalloc too in the near future?