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Date: Mon, 20 Sep 2010 12:07:06 +0200
From: Dimitry Andric <dim@FreeBSD.org>
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To: Dmitry Krivenok <krivenok.dmitry@gmail.com>
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Cc: freebsd-current@freebsd.org
Subject: Re: buildworld + ccache trouble
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On 2010-09-20 10:43, Dmitry Krivenok wrote:
> Your patch works fine for me, thanks!

Note this patch is just a workaround for now, I'm still working on the
proper solution. :)


> However, I don't see any performance gain when using ccache:
...
> cache miss                        225341
...
> cache miss                        362669
...
> Number of cache hits is very low.

Since ccache depends on the results of preprocessing being exactly the
same every time, there could be something in your setup and/or way of
updating that changes them during each update.

You can experiment with adding '-save-temps' to your compile flags, to
see if any resulting .i files unexpectedly change after you update your
source tree.