[cairo] fixing Cairo's FreeType multi-threaded usage

[David Turner]

Hi Jan,

no, this is not normal at all; I'm running my desktop on this patch and
haven't seen any regression in performance. Are you sure your merge happened
without conflicts ?

the long story is that some of the intermediate commits in the patchset do
produce correct behaviour and very poor performance, but this is normally
fixed in later ones.

In the event your merge didn't work correctly, you could be left in one of
these hideously slow cases. I've just checked the patchset file, and the
changes described there seem ok.

Could you give more details about your test cases ? it may be interesting.

Regards,

- David


On Sat, 3 Mar 2007 01:47:49 +0100 (CET), "Jan Slupski" <jslupski at juljas.net> said:
> On Wed, 28 Feb 2007, David Turner wrote:
> 
> > Hello,
> >
> > here's the first version of my patches to fix Cairo's usage of FreeType with multiple
> > threads. It's rather big, so I'll summarize things here a little:
> 
> Hi David,
> 
> I tried your patches against the current git cairo (latest commit
> fed13e77e1de071ddaaf829aced10b02f6bc8c90).
> 
> Is it expected that cairo with these patches runs *much* slower
> than without? I'm running simple test case and it seems to be
> 8+ times slower even in single thread.
> 
> Is there anything special I should do (i.e. revert some already
> merged patches)?
> 
> I'll try to figure out what exactly caused the slowdown, but any hints
> are apperciated...
> 
> I have used default setup (./autogen.sh; make) and
> fontconfig 2.4.2, freetype 2.1.7 & 2.3.1
> 
> 
> > - the cairo_ft_ functions do implement the current Cairo behaviour regarding
> >  font options (i.e. the FontConfig backend ignores user-provided options for
> >  antialiased setting, extracting those from the original FcPattern instead)
> 
> It's OT here, but I absolutely agree with you that ignornoring
> user-provided
> options is... strange decision?
> 
> Thanks,
> Jan
> 
> 
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>     | |_| |\ |  S L U P S K I             jslupski at juljas.net
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