Contact emailsah...@chromium.org ExplainerAt the moment, V8 compiles WebAssembly modules by first compiling all functions with the baseline compiler Liftoff, and then immediately compiling all functions with the optimizing compiler TurboFan, see https://v8.dev/docs/wasm-compilation-pipeline. On some websites we see that TurboFan compilation can block JavaScript workers from execution. With WebAssembly dynamic tiering we want to reduce the CPU time of TurboFan compilation by only optimizing functions which were already executed a few times.
SpecificationThis feature is just a new implementation of an already implemented specification. Summary With WebAssembly Dynamic Tiering, an heuristic decides which functions of a WebAssembly module get optimized, and when the optimization is triggered. This is an improvement to the existing eager optimization approach, where all functions get optimized immediately after baseline compilation is finished. WebAssembly Dynamic Tiering reduces the resource consumption of the optimizing compiler, and prevents the compiler from competing with the web application for resources. Blink componentBlink>JavaScript>WebAssembly <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3EJavaScript%3EWebAssembly> TAG reviewNot applicable TAG review statusNot applicable Risks WebAssembly dynamic tiering may lead to unexpected performance regressions. Interoperability and Compatibility Gecko: No signal WebKit: No signal Web developers: No signals Goals for experimentation The goal of the experiment is to allow important partners to experiment with the performance impact of WebAssembly dynamic tiering. This feature may change the startup behavior of WebAssembly code significantly, which is why we would like to experiment in the guarded environment of an origin trial first. Reason this experiment is being extended Ongoing technical constraints Debuggability Debugging behavior does not change Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, Chrome OS, Android, and Android WebView)?Yes Is this feature fully tested by web-platform-tests <https://chromium.googlesource.com/chromium/src/+/master/docs/testing/web_platform_tests.md> ?Yes Flag nameWebAssemblyDynamicTiering Requires code in //chrome?False Estimated milestones No milestones specified Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5685307493056512 This intent message was generated by Chrome Platform Status <https://www.chromestatus.com/>. -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to blink-dev+unsubscr...@chromium.org. To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAELSTveTudJkMbuBMyZ%2BZTv334audVik78gEJTzmjym4X6wJTg%40mail.gmail.com.
