Can you buy chips with that many cores, or are these instances aggregations of multiple chips?
Nick On Fri, Aug 5, 2016 at 9:01 AM, Gregory Szorc <g...@mozilla.com> wrote: > I've been playing around with various Amazon EC2 instances lately. They > offer a x1.32xlarge instance that features 128 vCPUs. So I did what any > engineer with access to a corporate AWS account would do: I obtained an > instance and measured how long it took to build Firefox! > > $ time ./mach build > ... > Overall system resources - Wall time: 237s; CPU: 37%; Read bytes: 626688; > Write bytes: 15316516864; Read time: 32; Write time: 2306432 > > real 3m59.590s > user 172m42.840s > sys 12m49.444s > > According to `dstat`, we do manage to saturate all available CPU cores and > get 0% idle CPU for a large chunk of the "compile" tier. > > I think that's impressive. Even more impressive is there were no race > conditions! The build system has come a long way. > > It's worth noting that a c4.8xlarge (which "only" has 36 vCPUs) can do a > full build in 5 minutes, only a minute slower. Some of that is due to a > higher clock speed. But most of that is due to the reality that there are > still large chunks of the build where we can't saturate all available cores. > In particular, there are long periods with low core utilization: > > * during configure > * between the "export" and "compile" tiers (WebIDL and IPDL processing delay > start of compile tier) > * during libxul linking > > Just thought people would like to know how well C++ compiling scales in our > build system these days. We've come a long way. > > _______________________________________________ > dev-builds mailing list > dev-builds@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-builds > _______________________________________________ dev-builds mailing list dev-builds@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-builds
