long-term ccache statistics for a portage-dedicated instance

[robbat2]

Migrating data and cleaning up my old desktop display head machine, I decided to check out my ccache statistics. This is a very old cache, having first started 2006-01-13. The oldest item in the present cache is 2008-01-12, but the statistics are valid for the entire period. hits 229k and 834k misses = approximately 21% hit rate. This wasn't any crazy repeated compiling of my own code, just a dedicated ccache directory for Portage to use.

cache hit                         228637
cache miss                        834113
called for link                   100293
multiple source files                526
compile failed                     20645
ccache internal error                 14
preprocessor error                 12425
cache file missing                     9
bad compiler arguments                 1
not a C/C++ file                   39097
autoconf compile/link             183802
unsupported compiler option        34481
no input file                      96690
files in cache                    204344
cache size                           1.8 Gbytes
max cache size                       2.0 Gbytes

Comments

High hit ratio due to FEATURES='test'

[(Anonymous)]

On my system I have a hit ration of about 50% because I have FEATURES='test', and on some packages, the tests take forever, on other (stable) packages, the tests fail. For the first case, the usual scenario is Control + C, FEATURES='-test' and reemerge, and this is the case where ccache comes in really handy.

Re: High hit ratio due to FEATURES='test'

[robbat2.livejournal.com]

The box was purely a desktop display head. It basically ran X, ssh, and a single xterm instance (fluxbox and urxvtd were run remotely).

My copy of ccache for the kernel, or my own development gets much higher rates, >=70%.