Deepti, what did you mean by "ongoing standardization effort"? Is the API shape still being discussed?
On Thu, 2 Apr 2020 at 14:12, Yoav Weiss <y...@yoav.ws> wrote: > I'm wondering if there's something preventing partners from implementing > SIMD versions of their applications with the behind-the-flag implementation? > > I'm assuming you already have some partners lined up for the experiment. > Would they be able to develop using the flagged implementation? That would > enable us to start the origin trial when they're ready, and as a result, > have a shorter trial which purpose is to gather real life usage metrics. > > On Fri, Mar 27, 2020 at 11:02 PM Deepti Gandluri <gdee...@chromium.org> > wrote: > >> Hi Mounir, >> >> The reason for a longer trial here is that this proposal is somewhat >> large, and while enabling auto-vectorization can give some performance >> benefits, to really experiment with this applications may have to rewrite >> their existing code that uses native SIMD intrinsics to use portable Wasm >> intrinsics (example: Emscripten SIMD intrinsics header >> <https://github.com/emscripten-core/emscripten/blob/master/system/include/wasm_simd128.h>), >> or builtins that map to Wasm operations. >> >> The intent is to build in enough time for new applications to experiment >> with this in parallel to ongoing standardization effort in the WebAssembly >> CG. The ballpark estimate I've used here is from previous applications >> experimenting with SIMD, with some buffer to gather data. That said, I do >> understand that this is a longer trial than is usual, so would be open to >> adjusting the timeline based on concerns. >> >> Thanks, >> Deepti >> >> On Friday, March 27, 2020 at 1:29:09 PM UTC-7, Mounir Lamouri wrote: >>> >>> Hi Deepti, >>> >>> This Intent to Experiment looks good, though, I'm wondering why this is >>> expected to run for 5 releases, which is roughly 6 months. Is there >>> something specific we are concerned about and that this timeline aims to >>> solve? >>> >>> -- Mounir >>> >>> On Fri, 27 Mar 2020 at 07:22, Deepti Gandluri <gdee...@chromium.org> >>> wrote: >>> >>>> Contact emails >>>> >>>> gdee...@chromium.org, nattes...@chromium.org, z...@chromium.org >>>> >>>> >>>> Spec >>>> >>>> Overview document: >>>> https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md >>>> >>>> Proposal directory: >>>> https://github.com/WebAssembly/simd/tree/master/proposals/simd >>>> >>>> Tag review: https://github.com/w3ctag/design-reviews/issues/487 >>>> >>>> >>>> Summary >>>> >>>> The WebAssembly SIMD proposal defines a portable, performant subset of >>>> SIMD operations that map to vector instructions that are available across >>>> most modern hardware platforms. >>>> >>>> >>>> This is purely a WebAssembly performance feature that adds WebAssembly >>>> operations and does not affect web API behavior, but is still useful for >>>> developers to be aware of as it can change performance characteristics of >>>> applications using WebAssembly. >>>> >>>> >>>> Link to “Intent to Prototype” blink-dev discussion: >>>> >>>> This links to the Intent to Implement discussion for Simd.js >>>> <https://groups.google.com/a/chromium.org/forum/#!searchin/blink-dev/Simd.js%7Csort:date/blink-dev/rhPPSQVodq0/zr4HRxXjBgAJ>, >>>> which was the basis for the WebAssembly SIMD. The Spec section above has >>>> updated links for WebAssembly SIMD, as well as the Tag review. >>>> >>>> >>>> Goals for experimentation >>>> >>>> Performance: >>>> >>>> The goal for this experiment is to determine the performance benefit of >>>> having WebAssembly SIMD enabled applications in production code, and >>>> determine real world performance numbers. We currently have data from >>>> isolated benchmarks, and demos, but these do not always reflect real world >>>> usage. >>>> >>>> >>>> API Shape: >>>> >>>> The SIMD proposal currently consists of a set of operations that are >>>> well supported across most modern hardware platforms. The set of >>>> instructions available on hardware is large and varied, and we are looking >>>> for feedback on whether this portable subset is sufficient for a cross >>>> section of applications. >>>> >>>> >>>> Experimental timeline >>>> >>>> M84-M89 >>>> >>>> >>>> Any risks when the experiment finishes? >>>> >>>> The risk is a drop in performance for sites that were enhancing >>>> performance using WebAssembly SIMD operations. >>>> >>>> >>>> Ongoing technical constraints >>>> >>>> None. >>>> >>>> >>>> Debuggability >>>> >>>> WebAssembly SIMD needs debugging support in devtools for 128-bit >>>> values, as well as baseline compiler support in V8. Both of these efforts >>>> are ongoing. (Tracking bugs: crbug.com/v8/10347, crbug.com/v8/9909) >>>> >>>> >>>> Will this feature be supported on all five Blink platforms supported by >>>> Origin Trials (Windows, Mac, Linux, Chrome OS, and Android)? >>>> >>>> Yes. >>>> >>>> >>>> Link to entry on the feature dashboard <https://www.chromestatus.com/> >>>> >>>> https://www.chromestatus.com/feature/6533147810332672 >>>> >>>> -- >>>> 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/e4010247-bb4c-47a4-9b82-ea8188c3b232%40chromium.org >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/e4010247-bb4c-47a4-9b82-ea8188c3b232%40chromium.org?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- >> 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/e9f7ebf3-495e-46b7-82bd-a0f963f1625d%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/e9f7ebf3-495e-46b7-82bd-a0f963f1625d%40chromium.org?utm_medium=email&utm_source=footer> >> . >> > -- > 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/CACj%3DBEh8BicQHAygqbS0icM4R_%2B9qgzWmOS%2BmqtAicWiqZmRkA%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CACj%3DBEh8BicQHAygqbS0icM4R_%2B9qgzWmOS%2BmqtAicWiqZmRkA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- -- v8-dev mailing list v8-dev@googlegroups.com http://groups.google.com/group/v8-dev --- You received this message because you are subscribed to the Google Groups "v8-dev" group. 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