Poudriere works with a preconfigured cache size for ccache.

To check the current size, see /data/ccache/ccache.conf

To check the usage ratio, chroot into one of the (running) build jails or start one using poudriere jail -s -j jailname

There, just enter ccache -s

 

root@freebsd1:/ # ccache -s
cache directory                     /root/.ccache
primary config                      /root/.ccache/ccache.conf
secondary config      (readonly)    /usr/local/etc/ccache.conf
cache hit (direct)                 96792
cache hit (preprocessed)           32399
cache miss                        501831
called for link                    81061
called for preprocessing           17133
multiple source files                361
compiler produced stdout               8
compiler produced no output           18
compile failed                     27948
preprocessor error                 22857
can't use precompiled header         230
bad compiler arguments              5331
unsupported source language         2067
autoconf compile/link             141009
unsupported compiler option         2623
no input file                      41078
files in cache                     79464
cache size                           1.0 GB
max cache size                       4.0 GB

 

If you see the cache usage is anywhere close to 90% you might want to raise the limit.

In my case I've changed it from 1.1GB to 4GB by updating the ccache.conf.

 

As for the stats, you can see the hit rate (before raising the limit) was pretty exactly 25%.

(96792 + 32399) * 100 / 501831

It doesn't mean an exact 25% speedup of the whole poudriere run, but at least 25% of the compiler calls were pretty instantaneous.