[ccache] [patch] Massive performance degradation with direct mode due to bypassing filesystem cache with mmap (Mac/PPC)

Joel Rosdahl joel at rosdahl.net
Fri Aug 27 12:44:20 MDT 2010

On 2010-08-27 13:37, Christian Lohmaier wrote:
> reject in this case means: doesn't even attempt to cache it.
> random pick from ccache-log:
> Compiler option
> @__________________________________________________OOO/libaggmxi.dylib
> is unsupported
> [...]
> So it boils down to bad statistics (unsupported compiler option
> instead of called for link), and not "doesn't cache stuff it could
> cache".
> Adding -install_name to the set of options that require an argument
> should do the trick, then the @____ argument will not trigger the "is
> too hard" case.

I see. Yes, it seems reasonable to add it to get better statistics.

> Maybe even add -isysroot to that list, since that otherwise triggers
> "/Developer/SDKs/MacOSX10.4u.sdk is not a regular file, not
> considering as input file" in the log. But that (opposed to the linker
> one) would be merely cosmetics (would save a stat call)

Right. However, there seems to be many other Darwin-specific flags that
take an argument, and I don't think it's worth the effort adding such
options just to avoid a stat call.

-- Joel

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