Is there a reason why we aren't using LTO? On Fri, Apr 8, 2016 at 4:35 PM, Ted Mielczarek <t...@mielczarek.org> wrote:
> No. GCC *has* an LTO optimizer, but we're not using it. We're just doing > a PGO build. MSVC requires enabling LTO to use their PGO, so the > resulting build has both. > > -Ted > > On Fri, Apr 8, 2016, at 05:08 PM, Jeff Gilbert wrote: > > I thought Linux did LTO but not PGO? > > > > On Tue, Apr 5, 2016 at 3:53 PM, Mike Hommey <m...@glandium.org> wrote: > > > On Tue, Apr 05, 2016 at 09:02:09PM +0100, David Burns wrote: > > >> Below is a highlight of all work the build peers have done in the > last 2 > > >> weeks as part of their work to modernise the build infrastructure. > > >> > > >> Since the last report[1] a large number of improvements have landed in > > >> Mozilla Central. > > >> > > >> The build system now lazily installs test files. Before, the build > copied > > >> tens of thousands of test and support files. This could take dozens of > > >> seconds on Windows or machines with slow I/O. Now, the build system > defers > > >> installing test files until they are needed there (e.g. when running > tests > > >> or creating test packages). Furthermore, only the test files relevant > to > > >> the action performed are installed. Mach commands running tests > should be > > >> significantly faster, as they no longer examine the state of tens of > > >> thousands of files on every invocation. > > >> > > >> After upgrading build machines to use VS2015, we have seen a decrease > in > > >> build times[2] for PGO on Windows by around 100 minutes. This brings > PGO > > >> times on Windows in line with that of PGO(Strictly speaking this is > LTO) > > >> times on Linux. > > > > > > Just a nit: strictly speaking Windows builds do PGO+LTO, Linux builds > do > > > PGO, but not LTO. > > > > > > Mike > > > _______________________________________________ > > > dev-platform mailing list > > > dev-platform@lists.mozilla.org > > > https://lists.mozilla.org/listinfo/dev-platform > > _______________________________________________ > > dev-platform mailing list > > dev-platform@lists.mozilla.org > > https://lists.mozilla.org/listinfo/dev-platform > _______________________________________________ > dev-platform mailing list > dev-platform@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-platform > _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
