Hi Stephen - I've built v8 standalone at today's top-of-tree, the top of 3.27 branch (3.27.34.21), and your specific version 3.27.34.0) and all are fine.
I see _no_ perf degradation. This is on 'mipsel', a mips32r2 device with floating point. I've just checked a Chromium ToT Android build from mid-last week, and it looks fine also. I will pull a M37 release branch, and build that too. You are on 37.0.2062.0. I see Android stable is on 37.0.2062.117. Not that it should make any difference with this terrible perf drop you are seeing. I'll build both Android and Linux at 37.0.2062.0 and see what I find. I've not looked at your traces in detail yet, I've been just sanity-checking perf on the devices we usually test on. As far as debugging on your side, I suggest you do try v8 standalone. Also, I'm using gcc 4.8.1 for these tests, using the Mentor/Code-Sourcery lite toolchain available here: https://sourcery.mentor.com/GNUToolchain/package12215/public/mips-linux-gnu/mips-2013.11-36-mips-linux-gnu-i686-pc-linux-gnu.tar.bz2 paul > On Nov 3, 2014, at 3:43 PM, Paul Lind <[email protected]> wrote: > > Very sorry Stephen, that is crazy bad. We'll get on this immediately and get > it understood and fixed asap. > > paul > > >> On Nov 3, 2014, at 2:59 PM, Stephen <[email protected] >> <mailto:[email protected]>> wrote: >> >> Dear v8-users, >> >> We have a port of Chromium to a MIPS(el) embedded system, and are currently >> in the process of upgrading it from M31 (31.0.1650.61, v8 version >> 3.21.18.9[1]) to M37 (37.0.2062.0, v8 version 3.27.34.0[1]). In doing so, we >> have run into what seems to be a serious regression in V8 performance. >> Running the Octane benchmark >> (http://octane-benchmark.googlecode.com/svn/latest/index.html >> <http://octane-benchmark.googlecode.com/svn/latest/index.html>), these are >> the numbers on our platform for M31 and M37: >> >> M31: >> >> Richards: 1578 >> DeltaBlue: 951 >> Crypto: 1133 >> RayTrace: 1830 >> EarleyBoyer: 2347 >> RegExp: 256 >> Splay: 341 >> SplayLatency: 1434 >> NavierStokes: 1223 >> PdfJS: 580 >> Mandreel: 654 >> MandreelLatency: 649 >> Gameboy: 1112 >> CodeLoad: 756 >> Box2D: 501 >> zlib: 1769 >> Typescript: 887 >> Overall: 905 >> >> M37: >> >> Richards: 5.88 >> DeltaBlue: 3.66 >> Crypto: 21.4 >> RayTrace: 15.3 >> EarleyBoyer: 67.4 >> RegExp: 57.9 >> Splay: 55.5 >> SplayLatency: 487 >> NavierStokes: 36.6 >> PdfJS: 50.2 >> Mandreel: 4.60 >> MandreelLatency: 66.2 >> Gameboy: 1589 >> CodeLoad: 801 >> Box2D: 689 >> zlib: 2650 >> Typescript: 968 >> Overall: 87.0 >> >> Obviously we are rather concerned by these numbers - a 10x degradation in >> overall score, and nearly 300x in some benchmarks! SunSpider shows similar >> levels of regression - a 3x overall increase in time taken, and multiple >> 100x's in some individual benchmarks. >> >> I have begun to dig into some of the benchmarks, and am attaching traces >> taken against the Octane 'crypto' benchmark on M31 and M37 using the >> --js-flags="--perf" switch. The M37 version seems to spend an enormous >> amount of time in the 'am3' function: 16913 ticks (as opposed to 39 ticks in >> the M31 case). Might this indicate some sort of regression in MIPS math code? >> >> Are there any known performance regressions in v8 on MIPS(el) in M37, or any >> suggestions on how we can debug this further? Feel free to ask for further >> information/testing/etc, and I will do my best to provide! I have tried to >> build standalone ToT V8 for our platform, but ran into issues with warnings >> being converted to errors that I haven't dealt with yet. >> >> Thanks, >> Stephen >> >> [1]: According to http://omahaproxy.appspot.com/ >> <http://omahaproxy.appspot.com/> >> >> -- >> -- >> v8-users mailing list >> [email protected] <mailto:[email protected]> >> http://groups.google.com/group/v8-users >> <http://groups.google.com/group/v8-users> >> --- >> You received this message because you are subscribed to the Google Groups >> "v8-users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] >> <mailto:[email protected]>. >> For more options, visit https://groups.google.com/d/optout >> <https://groups.google.com/d/optout>. >> <v8_m37_crypto_trace.log><v8_m31_crypto_trace.log> > > > -- > -- > v8-users mailing list > [email protected] > http://groups.google.com/group/v8-users > <http://groups.google.com/group/v8-users> > --- > You received this message because you are subscribed to the Google Groups > "v8-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- -- v8-users mailing list [email protected] http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
