In the S&P review, we were wondering if the memory pressure case event was an event exposed to the web page or an internal Chrome event? In the latter case, there may be a potential for XS-Leaks.
Thanks! On Monday, March 20, 2023 at 3:57:24 PM UTC+1 Mike Taylor wrote: > LGTM to experiment in canary/dev. For clarity, how long do you plan to > experiment? > > (I don't think you need an LGTM in this case, > https://www.chromium.org/blink/launching-features/#origin-trials mentions > needing an LGTM to experiment on beta or stable - but thanks for sending > the intent!). > On 3/20/23 10:16 AM, Jiacheng Guo wrote: > > The spec says: > User agents may copy entries from one Document > <https://html.spec.whatwg.org/multipage/dom.html#document> object's list > of available images > <https://html.spec.whatwg.org/multipage/images.html#list-of-available-images> > to > another at any time > I believe the change is in line with the spec. It makes this behavior more > frequent. The spec does not define behavior for other resources for now. > The other involved resource types are stylesheet, fonts and scripts. It > would be desirable to add a description about MemoryCache for these > resources in the spec and allow cross-document reusing. For now I believe > it is acceptable to launch the experiment in dev and canary. > > We plan to launch the experiment in dev and canary in April. There are > concerns about the memory footprint increase introduced by the change so we > decide to hold the experiment in beta or stable. The experiment will > provide data for the tradeoff between memory consumption and load speed. If > the experiments in dev and canary show a positive impact on page loading > metrics, we plan to refine the resource saving strategy and launch with the > new implementation. > > On Mon, Mar 20, 2023 at 10:49 PM Mike Taylor <[email protected]> > wrote: > >> What are the desired timelines for the experiments? >> >> The design doc mentions only testing in dev and canary - do you plan to >> eventually experiment in beta or stable? >> On 3/17/23 2:08 PM, 'Jiacheng Guo' via blink-dev wrote: >> >> Contact emails [email protected] >> >> Explainer >> https://docs.google.com/document/d/1jcdXkoFBbdxmp_EYIrrOJvEgYd0hGBAr4Nbno7KWnIs/edit?usp=sharing >> >> Specification The feature is not web-spec related. >> >> Design docs >> >> https://docs.google.com/document/d/1jcdXkoFBbdxmp_EYIrrOJvEgYd0hGBAr4Nbno7KWnIs/edit?usp=sharing >> >> Summary >> >> To measure the impact of garbage collection on Blink memory cache and >> potential performance boost, we plan to keep strong references to loaded >> resources in the Blink memory cache. The change will serve as an estimation >> only project to collect data about the maximal cache hit rate with all >> resources available. >> >> >> Blink component Blink>Loader >> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3ELoader> >> >> TAG review >> TAG review is not required since the experiment changes the internal >> behavior of renderer and is transparent to the websites and web developers. >> >> Risks >> >> >> Interoperability and Compatibility >> >> Resource reference lifetime does not affect the behavior of the browser. >> We do not expect there to be interoperability or compatibility issues. >> >> *Gecko*: No signal >> >> *WebKit*: No signal >> >> *Web developers*: No signals >> >> *Other signals*: >> >> WebView application risks >> >> The change does not modify the behavior of web APIs >> >> Goals for experimentation >> >> The four configurations will be launched on dev/canary. The combinations >> are: * The control group. No strong reference to resources. * Save strong >> references for all resources of all types for all the pages. * Save strong >> references for only script, fonts and stylesheets for all pages. * Save >> strong references for all resources for only one page. * Save strong >> references for only script, fonts and stylesheets for only one page. We >> will evaluate the following metrics under different configurations * Core >> web browsing metric (FCP/LCP etc) * Cache hit rate: >> Blink.MemoryCache.RevalidationPolicy * Memory footprint * Crash Rate >> >> >> Reason this experiment is being extended >> >> Ongoing technical constraints >> >> Debuggability >> >> 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/+/main/docs/testing/web_platform_tests.md> >> ? No, resource reference lifetime in blink is invisible to the websites. >> >> Flag name MemoryCacheStrongReference for the overall configuration. >> MemoryCacheStrongReferenceSingleUnload and >> MemoryCacheStrongReferenceFilterImages for sub configurations >> >> Requires code in //chrome? False >> >> Tracking bug https://crbug.com/1409349 >> >> Estimated milestones >> >> The feature is for experiment only. We do not expect to launch it to >> stable as it is. If the experiment provides positive results, we will move >> on to further refine the resource lifetime management strategy in Blink. >> >> Link to entry on the Chrome Platform Status >> https://chromestatus.com/feature/5196823129489408 >> >> This intent message was generated by Chrome Platform Status >> <https://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 [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAJQw1NwNzokqhvwtnrV-J-8BeMeRjfC-cvkXMBmZYK4Vej%3DX%2Bg%40mail.gmail.com >> >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAJQw1NwNzokqhvwtnrV-J-8BeMeRjfC-cvkXMBmZYK4Vej%3DX%2Bg%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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