https://aws.amazon.com/about-aws/whats-new/2016/05/now-available-x1-instances-the-largest-amazon-ec2-memory-optimized-instance-with-2-tb-of-memory/ has the details. 4 x 18 cores+hyperthreads in a multiprocessor configuration yields 128 vCPUs. (The subject line is wrong: this was "only" a 64 core machine.)
> On Aug 4, 2016, at 20:49, Nicholas Nethercote <n.netherc...@gmail.com> wrote: > > 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
