Does this mean that snapshotting for embedders has some support now? And by support, I mean a bit of embedder documentation, and, a documented API in v8.h. Because that could/would be interesting.
On Fri, Jan 30, 2015 at 5:07 AM, Yang Guo <yang...@chromium.org> wrote: > You are welcome to play around with code caching. Take a look at > CompileString in src/d8.cc or test/cctest/test-serialize.cc for examples. > > On Wednesday, January 28, 2015 at 6:01:22 AM UTC+1, Jiang Kelvin wrote: >> >> Thanks for sharing the details of technology. Maybe it is also really hard >> to return a kind of serializable compiled code and let the embedder to >> handle(e.g. store) it. >> I just thought about that if the "installation" process can do more. (For >> example if windows wanna run their applications on lots of devices based on >> X86/ARM/MIPS, I think a reasonable way is that do the back-end compiling >> works and linkings when installing.) >> >> On Tue, Jan 27, 2015 at 5:54 PM, Jakob Kummerow <jkum...@chromium.org> >> wrote: >>> >>> It's complicated. >>> >>> V8 has a so-called "snapshotting" mechanism which is used to speed up >>> startup. Recently people have been working on using it to cache other code >>> as well. >>> >>> That said, this is no silver bullet, as there are a number of inherent >>> challenges: >>> - dynamic languages like JavaScript are not well-suited for ahead-of-time >>> compilation >>> - generating optimized code depends on having collected type feedback, so >>> it can't happen up front; it also by definition bakes in a number of >>> non-cacheable assumptions >>> - generating non-optimized code, on the other hand, is relatively fast >>> anyway (unless there's a huge amount of it), so caching it only helps so >>> much >>> - assuming you have a working caching mechanism, you need reasonable >>> rules when to use it, how much disk space you're giving it, how you're >>> making sure it isn't stale, and so on. >>> - caching generated code doesn't affect sustained performance (possibly >>> on the contrary), it can only improve startup time. >>> >>> So having an explicit and time-consuming "installation"/pre-compilation >>> phase for JS packages isn't going to happen. However, more automatic caching >>> under the hood is something you're likely to see in the future (regardless >>> of where scripts came from -- there's no reason this couldn't work with >>> regular scripts found on web sites.) >>> >>> >>> On Tue, Jan 27, 2015 at 3:33 AM, Jiang Kelvin <leiy...@gmail.com> wrote: >>>> >>>> Not all js files are online, such as the js files in >>>> extensions/web-apps/application-cache. If we can save the result of >>>> compilation when installing or upgrading them, and just load and run the >>>> binary codes when calling a js function(think about the ART of Android), is >>>> it possible to improve performance? >>>> >>>> -- >>>> -- >>>> v8-users mailing list >>>> v8-u...@googlegroups.com >>>> 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 v8-users+u...@googlegroups.com. >>>> For more options, visit https://groups.google.com/d/optout. >>> >>> >>> -- >>> -- >>> v8-users mailing list >>> v8-u...@googlegroups.com >>> http://groups.google.com/group/v8-users >>> --- >>> You received this message because you are subscribed to a topic in the >>> Google Groups "v8-users" group. >>> To unsubscribe from this topic, visit >>> https://groups.google.com/d/topic/v8-users/2Gjwvzhjs0Q/unsubscribe. >>> To unsubscribe from this group and all its topics, send an email to >>> v8-users+u...@googlegroups.com. >>> For more options, visit https://groups.google.com/d/optout. >> >> > -- > -- > v8-users mailing list > v8-users@googlegroups.com > 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 v8-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- -- v8-users mailing list v8-users@googlegroups.com 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 v8-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
