Hi, In the coming days and weeks, there are going to be a few changes to how we do automated build on Windows, all in the interest of faster build times: - Shared compilation cache is going to be deployed soon(ish). We currently have no compilation cache at all on windows, and we're going to have a cache shared by all slaves. - Switching builds to mozmake.
The latter is the one that makes the biggest change to developers: we will effectively stop using pymake on automation. Usually, such things follow with quick degradation, so if you're still using pymake for your local builds, please consider switching to mozmake soon. If you are using "mach build", this happens automatically if mozmake is installed on your machine. Mozmake comes in MozillaBuild 1.9.0pre posted a few months ago by RyanVM, and there shortly will be a MozillaBuild 1.9 release with a refreshed mozmake build. Upgrading to MozillaBuild 1.9 when it's released will get you mozmake builds automatically, if you're using "mach build". If you're still calling pymake directly, please run mozmake instead. Let me also give another incentive for the switch, besides decreasing the chances of build breakage, by telling you why we're switching builds to mozmake and why we didn't do it earlier. When we initially released mozmake, we set up a disposable branch using it and it turned out not to create massive wins on automation. There was still a local benefit from the use of "mach build binaries", but automation couldn't benefit from that. But after that experimentation, we've been switching to unified compilation, which helped making builds faster by having the compiler spend less time doing the same things in different files. But, it turns out, it also made the pymake backend less efficient, because the pymake backend still traverses directories without much parallelism, and now many directories are only compiling one or two files, which means we're not saturating the CPU when compiling. Which we do when using mozmake. Recent try pushes show switching from pymake to mozmake gets our automated builds (only the build part, excluding packaging, hg cloning, etc.) down from ~2900 seconds to ~1900 seconds (and sometimes even down to ~1700 seconds, for some reason). That's around a 35% build time drop. Also noteworthy, upcoming build system changes that are expected to further improve buils times, are likely to either break or make pymake builds slower than they are now. For all these reasons, please seriously consider switching to mozmake. Cheers, Mike _______________________________________________ dev-platform mailing list [email protected] https://lists.mozilla.org/listinfo/dev-platform
