On Wed, Oct 28, 2009 at 10:54 AM, Jens Alfke <s...@chromium.org> wrote:
>
> On Oct 27, 2009, at 9:10 PM, Mike Belshe wrote:
>
> From a performance perspective, it may be critical to use tcmalloc to match
> safari performance. It was literally a 50% speedup on most of the DOM perf
> when running on WinXP.
>
>
> Yeah, I've profiled some of the Dromaeo benchmarks, and the DOM-mutation
> test in particular is spending huge amounts of time in malloc and free.
>
> Should I open a bug on this task, then?
>
SGTM.
>
> I suspect this will use the version of TCMalloc which is embedded in WTF.
> I'd recommend against this approach. We should try to use a single
> allocator for the entire app
>
>
> I agree; no sense linking in two different versions of tcmalloc.
>
> There is a disadvantage. I suspect Apple is farther along in optimizing
> the mac-specific optimizations of tcmalloc than the google3 guys are.
>
>
> I would say more generally "*client*-specific optimizations". Some of the
> recent memory-bloat issues found by the Memory taskforce (jamesr in
> particular) show that baseline tcmalloc is tuned for server environments
> where memory footprint is much less of an issue.
>
That may be true too, but, having looked at what they've done, I don't think
they've done a lot to fix this problem (yet). Chrome now uses a lot less
memory than safari.
I was really pointing out the mac-port potential problems. See tcmalloc's
TCMalloc_SystemAlloc() routines ported to the mac. I don't know that the
google3 tools has a mac version at all? tcmalloc was designed for linux
which leverages a cute trick using MADV_DONT_NEED (is this MADV_FREE_REUSE
on the mac?) to release memory (sorta). It may be that we can port the
webkit implementations for mac back to the google3-perftools open source
project, and also make it release memory better.
If you pick up this task, you can ask Jim, James or me for details; I think
we've all been fairly deep into tcmalloc to help get you ramped up quickly.
Mike
> —Jens
>
--~--~---------~--~----~------------~-------~--~----~
Chromium Developers mailing list: chromium-dev@googlegroups.com
View archives, change email options, or unsubscribe:
http://groups.google.com/group/chromium-dev
-~----------~----~----~----~------~----~------~--~---
