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), 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/ -- -- 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.
v8_m37_crypto_trace.log
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v8_m31_crypto_trace.log
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