> On Aug 29, 2017, at 11:03 AM, Geoffrey Garen <gga...@apple.com> wrote: > >> I worry about adopting unity build because while it makes clean builds >> faster, it also slows down incremental builds. As a developer, I rarely do >> clean builds, I mostly do incremental builds so this would likely make my >> experience worse? > > We have some preliminary data that says incremental builds will be OK, but > not a full benchmark. > > Here’s a full benchmark I propose to test incremental builds: > > Start 7 days ago in SVN history. Do a clean build. > > SVN update forward by 24 hours. Do an incremental build. Time this > build. > > Repeat 7 times. Average the results. > > I think we should run this benchmark per project as we adopt unity builds, > starting with WTF. > > In the beginning, when we adopt unity builds for WTF and then JavaScriptCore, > the benchmark can build just these projects and stop. Once we get to WebCore > and WebKit, the benchmark will take longer. Oh well. > > If we get the bundling right, this benchmark should show obvious speedups. If > it shows no speedup or a slowdown, we’ve done something wrong and we need to > reconsider.
This isn’t the scenario I find myself in most often. A much more common scenario is working on a change; touch one or two files, and then compile and test/debug. Rinse and repeat. - Sam _______________________________________________ webkit-dev mailing list webkit-dev@lists.webkit.org https://lists.webkit.org/mailman/listinfo/webkit-dev
