[Webkit-unassigned] [Bug 33178] Segmented SharedBuffer: SharedBuffer doesn't have to be a flat memory block

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=33178





--- Comment #6 from Yong Li <yong.li.webkit at gmail.com>  2010-01-04 13:29:14 PST ---
(In reply to comment #3)
> (From update of attachment 45821 [details])
> Looks OK. But with no clients using the getSomeData function, it seems like
> it's scaffolding for some future work and functions like getSomeData are not
> tested. And this change will make things less efficient until the major clients
> adopt.

I have 3 more patches that make all script decoders, jpeg decoder and png
decoder support decoding from segmented SharedBuffer. Will post them soon.

> 
> Do you know what adding this temporary extra work does to page loading time? I
> don't want to get stuck with that.

Probably it's because it doesn't need extra memory copying. But I'm not sure. I
did the test just because I want to make sure it doesn't slow down desktop
browsers.

> 
> This patch also changes behavior when running out of memory. The new code will
> abort when running out of memory, whereas the old code would drop data. I think
> that probably should be changed in a separate patch rather than as a side
> effect of this one.

The current patch calls fastMalloc and I remember fastMalloc calls abort() upon
OOM already. In the future, the allocation of segments can be done in other
ways for better performance. We could directly allocate a page of virtual
memory although I'm not sure if it helps.


Thanks for all suggestions and corrections! I'll modify the code and update the
patch soon

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.