Re: [v8-users] Microoptimizing message handling
On Fri, Apr 19, 2019 at 9:16 AM J Decker wrote: > > A question came to mind about the resolution of the 'compilation' of code.. I > have message handlers that receive an object with a standard field 'op'. > Then for each 'op' that can be processed I have an if test and a small amount > of code to handle the message (either inline or calling a function). > > Would it be better to call a function for each message handler, or is the > code within the if block consider a specific type of message? > Given that there is time lost to just calling a function and creating its > closure too... V8 emits ICs (inline caches) inside the if block. IOW, the simple solution should be best. :-) -- -- 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.
Re: [v8-users] Microoptimizing message handling
Optimized compilation happens on a per-function basis. A large function with many branches (if/else or switch), some of which are only executed rarely, tends to cause repeated deoptimizations (some branches have been executed enough to make the function hot, it gets optimized, then one of the as-yet unexecuted branches is hit the first time, causing a deopt; repeat). *If* you are running into that issue (you'll have to measure), then moving *every handler* out into its own function *could* indeed help (you'll have to measure). There's also always a chance that it doesn't matter in practice (i.e. the difference shows up in a microbenchmark or with tracing tools, but is not measurable in your real app). On Tue, Apr 23, 2019 at 12:45 PM Ben Noordhuis wrote: > On Fri, Apr 19, 2019 at 9:16 AM J Decker wrote: > > > > A question came to mind about the resolution of the 'compilation' of > code.. I have message handlers that receive an object with a standard field > 'op'. Then for each 'op' that can be processed I have an if test and a > small amount of code to handle the message (either inline or calling a > function). > > > > Would it be better to call a function for each message handler, or is > the code within the if block consider a specific type of message? > > Given that there is time lost to just calling a function and creating > its closure too... > > V8 emits ICs (inline caches) inside the if block. IOW, the simple > solution should be best. :-) > > -- > -- > 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.
[v8-users] Intent to Ship: Promise.allSettled
Contact Emails: gsat...@chromium.org Spec: https://tc39.github.io/proposal-promise-allSettled/ Summary: Promise.allSettled returns a promise that is fulfilled with an array of promise state snapshots, but only after all the original promises have settled, i.e. become either fulfilled or rejected. Interoperability and compatibility risk: This stage 3 proposal introduces a new static method on the Promise constructor. There is very low compat risk. Firefox: In development Safari: No signals Edge: No signals Is this feature fully tested? Yes, this feature passes V8's own mjsunit tests as well as all the test262 tests. Tracking bug: https://bugs.chromium.org/p/v8/issues/detail?id=9060 Link to entry on the Chrome Platform Status dashboard https://www.chromestatus.com/feature/5547381053456384 Requesting approval to ship? Yes. Note that since this is a V8/JS feature, this post is just an FYI to blink-dev — no sign off from Blink API owners is required. -- -- 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] Re: [v8-dev] Intent to Ship: Promise.allSettled
LGTM! On Tue, Apr 23, 2019 at 4:19 PM Sathya Gunasekaran wrote: > Contact Emails: > gsat...@chromium.org > > Spec: > https://tc39.github.io/proposal-promise-allSettled/ > > Summary: > Promise.allSettled returns a promise that is fulfilled with an array > of promise state snapshots, but only after all the original promises > have settled, i.e. become either fulfilled or rejected. > > Interoperability and compatibility risk: > This stage 3 proposal introduces a new static method on the Promise > constructor. There is very low compat risk. > > Firefox: In development > Safari: No signals > Edge: No signals > > Is this feature fully tested? > Yes, this feature passes V8's own mjsunit tests as well as all the > test262 tests. > > Tracking bug: > https://bugs.chromium.org/p/v8/issues/detail?id=9060 > > Link to entry on the Chrome Platform Status dashboard > https://www.chromestatus.com/feature/5547381053456384 > > Requesting approval to ship? > Yes. Note that since this is a V8/JS feature, this post is just an FYI > to blink-dev — no sign off from Blink API owners is required. > > -- > -- > v8-dev mailing list > v8-...@googlegroups.com > http://groups.google.com/group/v8-dev > --- > You received this message because you are subscribed to the Google Groups > "v8-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to v8-dev+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.
Re: [v8-users] Re: [v8-dev] Intent to Ship: Promise.allSettled
LGTM On Wed, Apr 24, 2019 at 6:01 AM 'Benedikt Meurer' via v8-dev < v8-...@googlegroups.com> wrote: > LGTM! > > On Wed, Apr 24, 2019, 02:05 Adam Klein wrote: > >> LGTM! >> >> On Tue, Apr 23, 2019 at 4:19 PM Sathya Gunasekaran >> wrote: >> >>> Contact Emails: >>> gsat...@chromium.org >>> >>> Spec: >>> https://tc39.github.io/proposal-promise-allSettled/ >>> >>> Summary: >>> Promise.allSettled returns a promise that is fulfilled with an array >>> of promise state snapshots, but only after all the original promises >>> have settled, i.e. become either fulfilled or rejected. >>> >>> Interoperability and compatibility risk: >>> This stage 3 proposal introduces a new static method on the Promise >>> constructor. There is very low compat risk. >>> >>> Firefox: In development >>> Safari: No signals >>> Edge: No signals >>> >>> Is this feature fully tested? >>> Yes, this feature passes V8's own mjsunit tests as well as all the >>> test262 tests. >>> >>> Tracking bug: >>> https://bugs.chromium.org/p/v8/issues/detail?id=9060 >>> >>> Link to entry on the Chrome Platform Status dashboard >>> https://www.chromestatus.com/feature/5547381053456384 >>> >>> Requesting approval to ship? >>> Yes. Note that since this is a V8/JS feature, this post is just an FYI >>> to blink-dev — no sign off from Blink API owners is required. >>> >>> -- >>> -- >>> v8-dev mailing list >>> v8-...@googlegroups.com >>> http://groups.google.com/group/v8-dev >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "v8-dev" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to v8-dev+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. >> > -- > -- > v8-dev mailing list > v8-...@googlegroups.com > http://groups.google.com/group/v8-dev > --- > You received this message because you are subscribed to the Google Groups > "v8-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to v8-dev+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.
