[Fontconfig] Re: performance patch: reduce stat () call if all cache files can be trusted

[Patrick Lam]

Takashi Iwai wrote:
> At Fri, 10 Feb 2006 17:16:17 -0500,
> Patrick Lam wrote:
> 
>>Takashi Iwai wrote:
>>
>>>However, such an option might be helpful for almost read-only sytems
>>>like thin clients. 
>>
>>It sounds like you'd want to merge all config files into one on a thin
>>client to get this perf gain without adding unsafe options.
> 
> Imagine all files are mounted as read-only over NFS, including fonts
> and font cache files.  Why bother to check and create local caches at
> each time you open apps in such a case?

So I've read the discussion in bug 148361 now.  I think it's definitely
leaving a lot of rope around for people to hang themselves with to trust
cache files; this isn't a failure mode that fontconfig ought to have, in
my opinion.

We're only talking about checking global (not local) caches; if they're
wrong, then we're in trouble.

If you really wanted to have an option like that, one kind of
off-the-wall way of limiting the damage would be to randomly check the
caches, say with a probability of 1%.  Then it would complain loudly if
you said the caches were up to date but they weren't.

pat