Files
poky/bitbake/lib
Richard Purdie 6b2cdc4b96 bitbake: siggen: Fix hashequiv performance issues
We're seeing huge slowdowns on large builds on the autobuilder. A qemux86 world
build was running really slowly, a primary feature was lots of rehashing going on
due to an sstate change which caused a rebuild when all output should be identical.

This was traced to the hundreds of thousands of calls to get_unihash() from
get_taskash(). If we simplify the unitaskhashes data structure, we can bypass
the function call and access the data directly. In local profile charts,
this significanly sped up process_possible_migrations(), both on profiles
and visually.

Whilst this change doesn't aid readability, it does solve an otherwise
huge performance issue.

(Bitbake rev: c4b8440f730c33eaf9f818b856ae81b2f1017fec)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
2019-12-12 13:15:00 +00:00
..
2016-06-02 08:24:02 +01:00