[v8-users] mksnapshot and warm_up
Hey, Can someone help me understand what the difference between a warm and cold snapshot is? I stumbled over `WarmUpSnapshotDataBlob` but I am not entirely sure how to make use of them via the mksnapshot-tools and what the sequence would be. Do I begin with a custom snapshot and then snapshot that snapshot again after its functions have been used? Thanks, Joh -- -- 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] mksnapshot and warm_up
On Thu, Mar 1, 2018 at 4:43 PM, Johannes Rieken wrote: > > Hey, > > Can someone help me understand what the difference between a warm and cold > snapshot is? I stumbled over `WarmUpSnapshotDataBlob` but I am not > entirely sure how to make use of them via the mksnapshot-tools and what the > sequence would be. Do I begin with a custom snapshot and then snapshot that > snapshot again after its functions have been used? > > Yes. See https://cs.chromium.org/chromium/src/v8/src/snapshot/mksnapshot.cc?l=177&rcl=fd158bc49d646d93a59cd07d07dfb9627bc94a30 for an example. The steps are also nicely explained here: https://cs.chromium.org/chromium/src/v8/src/api.cc?l=830&rcl=fd158bc49d646d93a59cd07d07dfb9627bc94a30 -- -- 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] mksnapshot and warm_up
Great! Thanks for the speedy reply. Looking at https://cs.chromium.org/chromium/src/v8/test/cctest/test-serialize.cc?type=cs&q=CustomSnapshotDataBlobWithWarmup&l=1167 makes me think/hope that functions are being compiled but state isn't changed (e.g. the assignment to `a` isn't persistent). Is that a correct assumption? On Thursday, March 1, 2018 at 5:16:37 PM UTC+1, Jakob Gruber wrote: > > On Thu, Mar 1, 2018 at 4:43 PM, Johannes Rieken > wrote: > >> >> Hey, >> >> Can someone help me understand what the difference between a warm and >> cold snapshot is? I stumbled over `WarmUpSnapshotDataBlob` but I am not >> entirely sure how to make use of them via the mksnapshot-tools and what the >> sequence would be. Do I begin with a custom snapshot and then snapshot that >> snapshot again after its functions have been used? >> >> > Yes. See > https://cs.chromium.org/chromium/src/v8/src/snapshot/mksnapshot.cc?l=177&rcl=fd158bc49d646d93a59cd07d07dfb9627bc94a30 > > for an example. > > The steps are also nicely explained here: > > https://cs.chromium.org/chromium/src/v8/src/api.cc?l=830&rcl=fd158bc49d646d93a59cd07d07dfb9627bc94a30 > > -- -- 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: Re: [v8-users] mksnapshot and warm_up
Thanks for emailing me! No, I haven’t been hacked :) I signed up for a spam filtering service called BitBounce. To deliver your email to my inbox, please click the link below. Thanks! https://bitbounce.com/pay_bitbounce_fee/332072661 BitBounce is a product by: Turing Technology, Inc. BitBounce.com Redwood City, CA -- -- 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] mksnapshot and warm_up
AFAIK that's correct. The polluted warmup context is thrown out, and a second clean context (with the now-compiled code) is serialized into the warmed up snapshot. On Thu, Mar 1, 2018 at 5:31 PM, Johannes Rieken wrote: > Great! Thanks for the speedy reply. Looking at https://cs.chromium.org/ > chromium/src/v8/test/cctest/test-serialize.cc?type=cs&q= > CustomSnapshotDataBlobWithWarmup&l=1167 makes me think/hope that > functions are being compiled but state isn't changed (e.g. the assignment > to `a` isn't persistent). Is that a correct assumption? > > On Thursday, March 1, 2018 at 5:16:37 PM UTC+1, Jakob Gruber wrote: >> >> On Thu, Mar 1, 2018 at 4:43 PM, Johannes Rieken >> wrote: >> >>> >>> Hey, >>> >>> Can someone help me understand what the difference between a warm and >>> cold snapshot is? I stumbled over `WarmUpSnapshotDataBlob` but I am not >>> entirely sure how to make use of them via the mksnapshot-tools and what the >>> sequence would be. Do I begin with a custom snapshot and then snapshot that >>> snapshot again after its functions have been used? >>> >>> >> Yes. See https://cs.chromium.org/chromium/src/v8/src/snapshot/mks >> napshot.cc?l=177&rcl=fd158bc49d646d93a59cd07d07dfb9627bc94a30 for an >> example. >> >> The steps are also nicely explained here: >> https://cs.chromium.org/chromium/src/v8/src/api.cc?l=830&; >> rcl=fd158bc49d646d93a59cd07d07dfb9627bc94a30 >> > -- > -- > 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. > Jakob Gruber Software Engineer jgru...@google.com Google Germany GmbH Erika-Mann-Straße 33 80636 München Geschäftsführer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg Diese E-Mail ist vertraulich. Falls sie diese fälschlicherweise erhalten haben sollten, leiten Sie diese bitte nicht an jemand anderes weiter, löschen Sie alle Kopien und Anhänge davon und lassen Sie mich bitte wissen, dass die E-Mail an die falsche Person gesendet wurde. This e-mail is confidential. If you received this communication by mistake, please don't forward it to anyone else, please erase all copies and attachments, and please let me know that it has gone to the wrong person. -- -- 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] Profiling: what is "LoadIC: A load IC from the snapshot"?
My prof output starts off with [JavaScript]: ticks total nonlib name 12065 22.7% 22.7% LoadIC: A load IC from the snapshot 27325.1%5.1% Builtin: StrictEqual and I was wondering, can anyone tell me what LoadIC is? Thanks! Andrew -- -- 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: Re: [v8-users] mksnapshot and warm_up
Thanks for emailing me! No, I haven’t been hacked :) I signed up for a spam filtering service called BitBounce. To deliver your email to my inbox, please click the link below. Thanks! https://bitbounce.com/pay_bitbounce_fee/4119332566 BitBounce is a product by: Turing Technology, Inc. BitBounce.com Redwood City, CA -- -- 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] Profiling: what is "LoadIC: A load IC from the snapshot"?
The thing that handles property loads (like foo.bar;). Seeing it take 22% is rare. Is your app heavy on polymorphic property loads? On Thu, Mar 1, 2018 at 9:44 AM Andrew Wilcox wrote: > My prof output starts off with > > [JavaScript]: >ticks total nonlib name > 12065 22.7% 22.7% LoadIC: A load IC from the snapshot >27325.1%5.1% Builtin: StrictEqual > > and I was wondering, can anyone tell me what LoadIC is? > > Thanks! > > Andrew > > -- > -- > 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.
Re: [v8-users] Profiling: what is "LoadIC: A load IC from the snapshot"?
> > can anyone tell me what LoadIC is? > > > The thing that handles property loads (like foo.bar;). Thank you Jacob! Seeing it take 22% is rare. Is your app heavy on polymorphic property loads? Yes, I'm writing an interpreter and it was doing a *lot* of instanceof checks. Since I don't have undefined or null values in my interpreter, rather than use x instanceof Foo I can instead give Foo instances a "type" property of e.g. 100 and use x.type === 100, which is faster. So indeed yes, now it's doing a lot of polymorphic property loads! :-) Makes perfect sense, thanks! -- -- 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] Profiling: what is "LoadIC: A load IC from the snapshot"?
Depending on usage patterns, you might see a further speed boost if you
split your objects into two parts, where one has the same shape for all
objects and the other is type dependent, roughly:
class Thing {
constructor(type, specific, ...) {
this.type = type;
this.other_common_field = ...;
// If type === 100, this is a Foo; if type === 101, it's a Bar; etc.
this.type_specific_stuff = specific;
}
}
var x = new Thing(100, new Foo(...), ...); // Maybe wrap in a factory?
if (x.type === 100) {
var data = x.type_specific_stuff.foo_field; // Both loads are
monomorphic, yay!
}
On Thu, Mar 1, 2018 at 12:31 PM Andrew Wilcox
wrote:
> can anyone tell me what LoadIC is?
>>
>>
>
>> The thing that handles property loads (like foo.bar;).
>
>
> Thank you Jacob!
>
>
> Seeing it take 22% is rare. Is your app heavy on polymorphic property
>> loads?
>
>
> Yes, I'm writing an interpreter and it was doing a *lot* of instanceof
> checks. Since I don't have undefined or null values in my interpreter,
> rather than use x instanceof Foo I can instead give Foo instances a
> "type" property of e.g. 100 and use x.type === 100, which is faster. So
> indeed yes, now it's doing a lot of polymorphic property loads! :-) Makes
> perfect sense, thanks!
>
> --
> --
> 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.
Re: [v8-users] Profiling: what is "LoadIC: A load IC from the snapshot"?
> > Depending on usage patterns, you might see a further speed boost if you > split your objects into two parts, where one has the same shape for all > objects and the other is type dependent > Oh interesting idea! Thanks! -- -- 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.
