[squeak-dev] Can we make computing the local variables in the debugger lazy?

Marcel Taeumel marcel.taeumel at hpi.de
Mon Nov 9 08:06:31 UTC 2020


Hi Eliot, hi Christoph.

How is the current state of this issue? We did some recent improvements in the debugger. Yet, the styling of context variables can be still rather slow. Is it still noticeable?

Best,
Marcel
Am 01.10.2020 23:14:48 schrieb Thiede, Christoph <christoph.thiede at student.hpi.uni-potsdam.de>:
Hi Eliot,

you can have an inspector field's title be styled by sending "shouldStyleName: true" to it. The styling itself, then, is performed by the Inspector in #fieldList (or just browse the senders of #shouldStyleName), where the styler is invoked. Before styling the field list, the styler is configured in #aboutToStyle:requestor:/#updateStyler:requestor: where self doItContext is passed to the styler.

So tl;dr: Styling is always applied late (after the field list is constructed), you cannot break it by caching the temp names earlier. :-)

Best,
Christoph
[http://www.hpi.de/]
Von: Squeak-dev <squeak-dev-bounces at lists.squeakfoundation.org> im Auftrag von Eliot Miranda <eliot.miranda at gmail.com>
Gesendet: Donnerstag, 1. Oktober 2020 20:33:08
An: The general-purpose Squeak developers list; Taeumel, Marcel
Betreff: Re: [squeak-dev] Can we make computing the local variables in the debugger lazy?
 
Hi Christoph,


On Wed, Sep 30, 2020 at 2:27 AM Thiede, Christoph <Christoph.Thiede at student.hpi.uni-potsdam.de [mailto:Christoph.Thiede at student.hpi.uni-potsdam.de]> wrote:

Hi Eliot,

> Can you point me to where in ContextInspector the emphasis for the temp vars is chosen?

By convention, inspector fields are defined in the category "fields - streaming". So you are probably searching for ContextInspector >> #streamTemporaryVariablesOn: or ContextVariablesInspector >> #streamTemporaryVariablesOn:?

I found this code; I don't see any text emphasis going on.  Where is the code that turns temp variables red when they're out of scope?  Marcel?

Looking forward to your optimization! :-)

Best,
Christoph
[http://www.hpi.de/]
Von: Squeak-dev <squeak-dev-bounces at lists.squeakfoundation.org [mailto:squeak-dev-bounces at lists.squeakfoundation.org]> im Auftrag von Eliot Miranda <eliot.miranda at gmail.com [mailto:eliot.miranda at gmail.com]>
Gesendet: Mittwoch, 30. September 2020 09:09:27
An: The general-purpose Squeak developers list
Betreff: Re: [squeak-dev] Can we make computing the local variables in the debugger lazy?
 
Hi Marcel,


On Tue, Sep 29, 2020 at 1:07 AM Marcel Taeumel <marcel.taeumel at hpi.de [mailto:marcel.taeumel at hpi.de]> wrote:

Hi Eliot, hi all!

I fixed the issue with Tools-mt.989. The logic was already there in #runUntil.

Can you point me to where in ContextInspector the emphasis for the temp vars is chosen?  I want to modify ContextInspector to cache the temp names for a given method because I believe this will speed up stepping a lot.  However I couldn't find where the emphasis is applied so I'm worried that my cache may break something.  If I can see where that is being done I have a better chance at avoiding breaking things.


Best,
Marcel
Am 19.09.2020 23:00:33 schrieb Levente Uzonyi <leves at caesar.elte.hu [mailto:leves at caesar.elte.hu]>:
Hi Christoph,

On Sat, 19 Sep 2020, Thiede, Christoph wrote:

>
> Hi Eliot,
>
>
> very nice finding once again! I #timeProfile'd the menu button action and as I expected, the most expensive operation is the shout styling by the new inspectors, including the decompilation of every method:

What was it exactly that you profiled?

The screenshot shows that 76.9% was spent in #initializeVariablesFromContext,
of which 52.5% of the time was spent in CompiledMethod(CompiledCode) >>
#getSource. The rest of the tree is not visible, but these methods have
nothing to do with parsing or styling, they initialize the parser and
normally should take <1 ms.

Also, why is the decompiler producing the source code?

>
>
> [IMAGE]
>
>
> First, when loading ShoutCore-ct.78 (Inbox), the speed doubles (but probably that's rather a problem with my sources file, see the thread about this commit).

You may want to try compiling a VM where FilePlugin's CreateFile does not
set the FILE_FLAG_SEQUENTIAL_SCAN flag, and see if it helps with file
reading performance.


Levente

>
> Second, we do not redraw the world while running to the selection, so we do not need to update the inspectors at all. I think we could split up #doStep into some #basicDoStep (which would perform the actual stepping logic) +
> some #updateContextDuring: (which would update the stack list and the inspectors), then we would need to trigger the updates only once from #runToSelection:.
> As an alternative, we could make this method a bit more complex but responsive by applying the same updating logic from #runUntil.
>
> What do you think? :-)
>
> Best,
> Christoph
>
> _________________________________________________________________________________________________________________________________________________________________________________________________________________________________
> Von: Squeak-dev im Auftrag von Eliot Miranda
> Gesendet: Samstag, 19. September 2020 20:17:12
> An: The general-purpose Squeak developers list; Taeumel, Marcel
> Betreff: [squeak-dev] Can we make computing the local variables in the debugger lazy?  
> Hi Marcel,
>
>     can we try and reduce the frequency at which we compute the variables in the context inspector in the debugger?  It is a noticeable performance hit.  I really like the user interface, but the performance hit is making
> debugging difficult.
>
> As an example use this:
>
> | samples sineTable sound |
> "1 second of A below middle C (220Hz). 16000 / 220 is 72.72 recurring"
> sineTable := SoundPlayer sineTable: 73.
> sineTable doWithIndex: "And let's not deafen anyone..."
> [:sample :index| sineTable at: index put: sample // 4].
> samples := SoundBuffer new: 16000.
> 1 to: samples size by: sineTable size do:
> [:i| samples replaceFrom: i to: (i + sineTable size - 1 min: 16000) with: sineTable startingAt: 1].
> 1 to: 146 do:
> [:i|
> samples at: i put: ((samples at: i) * i / 146) asInteger.
> samples at: 16001 - i put: ((samples at: 16001 - i) * i / 146) asInteger].
> sound := SampledSound
> samples: samples
> samplingRate: 16000.
> sound := MixedSound new
> add: sound pan: 0.25;
> add: sound pan: 0.75;
> yourself.
> sound computeSamplesForSeconds: sound duration
>
>
> Open a workspace in e.g. a 64-bit image prior to Tools-mt.965 (I used an image containing Tools-mt.942).  Debug the above in the workspace.  Position the cursor at "sound computeSamplesForSeconds: sound duration" and do "run
> to here".  It is essentially instantaneous.
>
> Now do the same in a contemporary trunk image.  It takes almost 6 seconds.
>
> I used to be able to click step as fast as I could and the system would keep up with me.  Now I find that if I click too fast I can accumulate excess clicks and when I stp clicking the system will continue stepping and go too
> far.
>
> I don't want to lose the feedback the new variables list gives us.  But I do find the performance hit tedious.  I wonder could we cache the list and only update it
> - when Morphic updates, and
> - when the context changes?
>
>
> _,,,^..^,,,_
> best, Eliot
>
>



--

_,,,^..^,,,_

best, Eliot



--

_,,,^..^,,,_

best, Eliot
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20201109/77377719/attachment.html>


More information about the Squeak-dev mailing list