Ccache
There's a wonderful tool for gcc
called ccache
. You can read about it at their home page.
If you're always compiling the same programs over and over again — such as trying out several kernel patches, or testing your own development — then ccache
is perfect. While it may take a few seconds longer to compile a program the first time with ccache
, subsequent compiles will be much, much faster.
Contents
Installation
Install ccache, available from the official repositories
Enable ccache for makepkg
To enable ccache when using makepkg edit /etc/makepkg.conf
. In BUILDENV
uncomment ccache
(remove the exclamation mark) to enable caching. For example:
BUILDENV=(fakeroot !distcc color ccache !xdelta)
Enable for command line
If you're compiling your code from the command line, and not building packages, then you'll still want to use ccache
to help speed things up.
For that, you need to change your $PATH
to include ccache
's binaries before the path to your compiler.
export PATH="/usr/lib/ccache/bin/:$PATH"
You may want to add this line to your ~/.bashrc
file for regular usage.
Enable with colorgcc
Since colorgcc is also a compiler wrapper, some care needs to be taken to ensure each wrapper is called in the correct sequence.
export PATH="/usr/lib/colorgcc/bin/:$PATH" # As per usual colorgcc installation, leave unchanged (don't add ccache) export CCACHE_PATH="/usr/bin" # Tell ccache to only use compilers here
Then colorgcc needs to be told to call ccache instead of the real compiler. Edit /etc/colorgcc/colorgccrc
and change the /usr/bin
paths to /usr/lib/ccache/bin
for all the compilers in /usr/lib/ccache/bin
:
/etc/colorgcc/colorgccrc
g++: /usr/lib/ccache/bin/g++ gcc: /usr/lib/ccache/bin/gcc c++: /usr/lib/ccache/bin/g++ cc: /usr/lib/ccache/bin/cc g77:/usr/bin/g77 f77:/usr/bin/g77 gcj:/usr/bin/gcj
Misc
Change the cache directory
You may want to move the cache directory to a faster location than the default "~/.ccache" directory, like an SSD or a ramdisk.
To do change the cache location:
export CCACHE_DIR=/ramdisk/ccache # Tell ccache to use this path to store its cache
CLI
You can use the command line utility ccache to...
Show statistics summary:
$ ccache -s
Clear the cache completely:
$ ccache -C