Enable sstate cache

sstate background

To speed up the build process, sstate provides a cache mechanism, where sstate files from server can be reused to avoid build from scratch if the producer and consumer of the sstate has same environment. With perfect case, we can achieve more than 80% time decreasing.

use sstate cache server

Another build machine is needed to produce the sstate file periodically. The default sstate files directory is sstate-cache under build dir, which is needed to be exported via NFS, http or ftp server.

On your local machine, change the conf/local.conf as following:

SSTATE_MIRRORS ?= "\
file://.* http://someserver.tld/share/sstate/"

for NFS server

SSTATE_MIRRORS ?= "\
file://.* file:///local/mounted/dir/sstate/"

Use local sstate cache

You can make all the builds pointing to the same SSTATE_DIR to share sstate files between them, like this:

SSTATE_DIR ?= "$/share/sstate-cache