firebug performance problem w/web application

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ak732

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Jul 21, 2009, 3:52:40 PM7/21/09
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All,

Firebug is awesome. Can't live without it. But in the versions after
1.2, I'm experiencing a performance problem so bad we cannot use
them. Wasn't a problem until FF3.5, where 1.2 is no longer
compatible.

I'm not really complaining so much as thinking I must have some setup
issue. There's no way that it can be this slow for everyone. Here
are the details...

We have a web application I mostly run/debug on localhost. It's a
single-page app, that renders data in grids that are inside draggable,
floating "windows" (divs) with all the various bells. All rendering
is handled via Javascript on the client, with all communication to the
server done via AJAX. It makes heavy use of jQuery.

When debugging, there are a lot of individual Javascript files that we
merge and min into a single file for distribution. But obviously I
need Firebug to work with the indivual files for debugging. There's a
single CSS file. And there are a lot of pretty small image files for
things like icons, backgrounds, etc.

On Firefox 3.0, w/Firebug 1.2x, everything in the app from initial
page load to dragging 1000x1000 px grids around to paging through huge
datasets is near instantaneous. Just very very fast.

On Firefox 3.0, w/Firebug 1.3x, everything slows down tremendously.
Just loading the initial page takes anywhere from 3-5 seconds on
localhost (used to be instant on localhost, <1s via fast DSL
connection). Most of the time seems to be during the loading of the
many small images and javascript source files. AJAX performance is
greatly slowed as well.

So we stuck with Firebug 1.2x and waited for each new Firebug release
to test if performance had improved. Now, with Firefox 3.5, w/Firebug
1.4x, things are perhaps even slower. No improvement, maybe even some
degradation.

I'm wondering if I'm the only one to see this significant performance
difference? Or is there perhaps some setting or system issue causing
the performance meltdown?

I'm running on a pretty fast laptop w/Windows Vista 32bit, 4GB RAM,
dual-core processor. And as I've said, since 1.2 is screamingly fast,
it doesn't seem like a hardware thing.

Note that even with all Firebug 1.4x panels disabled, performance is
still really, really slow as compared to 1.2

Things I've tried:

- creating a new profile
- installing Firefox 3.5
- ensuring that javascript.options.strict is set to 'false'
- disabling all panels for all sites

Has anybody else seen this very slow performance problem? Is there
something I can tweak to get the newer Firebug versions to work at a
more useable speed?

Thanks for any help.

Andy

johnjbarton

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Jul 21, 2009, 4:44:46 PM7/21/09
to Firebug
There have been a number of performance improvements since 1.2, based
on user reported test cases of performance problems. As far as I know
there is one current reported problem on the DOM panel. So currently
the feedback is "the performance is acceptable".

jjb

ak732

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Jul 21, 2009, 4:57:23 PM7/21/09
to Firebug
I did more digging and testing. I fixed my performance problem but
discovered something pretty strange and disturbing that might be
relevant to other performance issues I've seen posted.

Way back when FB1.3 came out, I had a number of problems w/it (initial
bugs that were later corrected) and one of the things I was told to do
was try running it in a newly created profile. So I did that and it
fixed some minor things, but had a major performance problem (the one
I posted about above). Since then, I've tested all updates in either
that new profile, or an even newer profile. In every case, the
performance problem existed.

But...

I had never actually tried to completely uninstall Firebug on the new
profile. So I did that today. And performance was still horrible
even w/out Firebug. So it was the new profiles, and not Firebug that
was the problem. Maybe.

To test that theory, I backed up my original profile, then upgrade it
from FB1.2 to FB1.4 and it's super fast

So now I'm left to wonder why my default profile is so damn fast,
while all newly created profiles are so damn slow. And some co-
workers also have very slow performance which I now suspect has to do
with their Firefox profile.

Very strange. Makes me wonder if everyone installing Firefox these
days is seeing greatly reduced performance due to some non-obvious (to
me at least) change in the default profile settings.

I mean, we're talking instantaneous site loading vs. 10 seconds for
this web application I'm talking about.

It's less noticeable on sites w/fewer resources to be loaded.
The"connecting to..." message shows up on the status bar a lot and
stays around a lot. So whatever the profile difference(s) are, they
seem related to slowing up connection speed.

Guess I'll try the Mozilla folks next.

ak732

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Jul 21, 2009, 6:06:37 PM7/21/09
to Firebug
After a bunch of digging, I found a Firefox performance tweak that
fixed the problem. Hopefully this will help some others. In summary,
I changed network.dsn.disableIPv6 from true to false.

1. Open Firefox 3.x.
2. Type “about:config” in the address bar and hit enter.
3. In the Filter bar, enter “network.dns”.
4. You should see a setting called “network.dsn.disableIPv6”. It’s
likely set to “false”.
5. Double-click the setting “network.dsn.disableIPv6” which changes it
to true.
6. Close your browser.
7. Reload the browser.
8. Run the app and it should be considerably faster.

This improved load times for our, admittedly resource-heavy, web
application by around a factor or 10. I suspect it might be a fix
that only matters on Windows Vista, maybe Win7. Anyway, it's easy
enough to try.

SteveG

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Jul 27, 2009, 2:12:52 AM7/27/09
to Firebug
I tried setting the network.dsn.disableIPv6 to true... but the DOM
inspector was still preforming very slow?
Are there any other workarounds that you know of?

johnjbarton

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Jul 27, 2009, 11:27:09 AM7/27/09
to Firebug
By 'the DOM inspector" do you mean:
1) The DOM panel
or
2) The inspect tool (that shows the blue rectangles and uses the
HTML Panel
?

jjb

ak732

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Aug 4, 2009, 10:38:34 AM8/4/09
to Firebug
@SteveG:

I am seeing pretty good performance across all tabs at this point. I
can pretty much just leave firebug on all the time now w/out seeing
any undue performance hit. At least on any sites I've visited
recently.

Note that the ipv6 fix had nothing to do with Firebug itself. It was
purely a WinVista/Firefox performance issue. I only thought it was
Firebug originally because it occurred coincidentally w/my creating a
new Firefox profile to try out the newer version of Firebug (and the
newer profiles are created w/ipv6 enabled by default, unlike the older
ones).

Prefontim

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Aug 4, 2009, 3:21:48 PM8/4/09
to Firebug
I am also getting extremely slow performance with Firebug 1.4.x on FF
3.0. Firebug 1.3.3 did not have this issue. I disabled all other
plug-ins, but that did not help. Then, I tested it on a new profile,
and that did not help either. Firebug is too slow to be usable at
this point. I will have to use 1.3.3 (which is also almost too buggy
to be usable) for now.

Ed Abrams

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Aug 5, 2009, 1:32:48 PM8/5/09
to Firebug
Hello,

Here is my platform: Mac OSX Leopard (10.5.7).

Here is my browser: Firefox 3.5.2 (Build identifier: Mozilla/5.0
(Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1.2) Gecko/20090729
Firefox/3.5.2)

Here is my Firebug: 1.4.2

Problem: Crazy-bad performance in any window under test case

Test case:
* open firefox 3.5 and several tabs
* in one tab, go to gmail.com
* disable firebug
* go to gmail.com
* verify that performance in all cases is normal
* enable firebug
* enable every firebug panel EXCEPT console (disabled)
* verify that performance in all cases is normal
* enable the CONSOLE
* in gmail, click 'compose message'
* start typing

PROBLEM: the performance has become so bad that the characters you're
typing only appear at a rate of 1 character per second. Every other
tab and window is also performance-hit. If you try, you can get the
'stop script' dialog to appear, which cites a Firebug script, lib.js,
at line 1176 (I think -- I should double check) as being the lagging
line.

I hope this helps.

-Eddie

johnjbarton

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Aug 5, 2009, 2:08:44 PM8/5/09
to Firebug
Eddie, please install Firebug 1.4X.2, open the tracing window with
ERRORS set, and repeat the test, post the trace on our bug report
list.
More info: http://groups.google.com/group/firebug/web/faq-about-firebug.
I'll post back here with the results.
(The line number in 1.4.2 are different from 1.4X)
jjb

Ed Abrams

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Aug 9, 2009, 2:10:50 PM8/9/09
to Firebug
So far, with the tracing version, I have been able to reproduce the
problem and make my mac go crazy on the fans (CPU maxed out), but I
have not yet thrown the stop script exception that will give the line
number. I'll keep trying. It would be helpful to know whether other
people with the same platform can reproduce this.

-Eddie

On Aug 5, 2:08 pm, johnjbarton <johnjbar...@johnjbarton.com> wrote:
> Eddie, please install Firebug 1.4X.2, open the tracing window with
> ERRORS set, and repeat the test, post the trace on our bug report
> list.
> More info:http://groups.google.com/group/firebug/web/faq-about-firebug.
> I'll post back here with the results.
> (The line number in 1.4.2 are different from 1.4X)
> jjb
>
> On Aug 5, 10:32 am, Ed Abrams <zeroaltit...@gmail.com> wrote:
>
>
>
> > Hello,
>
> > Here is my platform: Mac OSX Leopard (10.5.7).
>
> > Here is my browser: Firefox 3.5.2 (Build identifier: Mozilla/5.0
> > (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1.2) Gecko/20090729
> > Firefox/3.5.2)
>
> > Here is my Firebug: 1.4.2
>
> > Problem: Crazy-badperformancein any window under test case
>
> > Test case:
> >  * open firefox 3.5 and several tabs
> >  * in one tab, go to gmail.com
> >  * disable firebug
> >  * go to gmail.com
> >  * verify thatperformancein all cases is normal
> >  * enable firebug
> >  * enable every firebug panel EXCEPT console (disabled)
> >  * verify thatperformancein all cases is normal
> >  * enable the CONSOLE
> >  * in gmail, click 'compose message'
> >  * start typing
>
> > PROBLEM: theperformancehas become so bad that the characters you're
> > typing only appear at a rate of 1 character per second.  Every other
> > tab and window is alsoperformance-hit.  If you try, you can get the
> > 'stop script' dialog to appear, which cites a Firebug script, lib.js,
> > at line 1176 (I think -- I should double check) as being the lagging
> > line.
>
> > I hope this helps.
>
> > -Eddie
>
> > On Aug 4, 3:21 pm, Prefontim <Prefon...@hotmail.com> wrote:
>
> > > I am also getting extremely slowperformancewith Firebug 1.4.x on FF
> > > 3.0.  Firebug 1.3.3 did not have this issue.  I disabled all other
> > > plug-ins, but that did not help.  Then, I tested it on a new profile,
> > > and that did not help either.  Firebug is too slow to be usable at
> > > this point.  I will have to use 1.3.3 (which is also almost too buggy
> > > to be usable) for now.
>
> > > On Aug 4, 10:38 am, ak732 <ask...@gmail.com> wrote:
>
> > > > @SteveG:
>
> > > > I am seeing pretty goodperformanceacross all tabs at this point.  I
> > > > can pretty much just leave firebug on all the time now w/out seeing
> > > > any undueperformancehit.  At least on any sites I've visited
> > > > recently.
>
> > > > Note that the ipv6 fix had nothing to do with Firebug itself.  It was
> > > > purely a WinVista/Firefoxperformanceissue.  I only thought it was
> > > > Firebug originally because it occurred coincidentally w/my creating a
> > > > new Firefox profile to try out the newer version of Firebug (and the
> > > > newer profiles are created w/ipv6 enabled by default, unlike the older
> > > > ones).
>
> > > > On Jul 27, 2:12 am, SteveG <sgehringdes...@gmail.com> wrote:
>
> > > > > I tried setting the network.dsn.disableIPv6 to true...  but the DOM
> > > > > inspector was still preforming veryslow?
> > > > > Are there any other workarounds that you know of?
>
> > > > > On Jul 21, 3:06 pm, ak732 <ask...@gmail.com> wrote:
>
> > > > > > After a bunch of digging, I found a Firefoxperformancetweak that

johnjbarton

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Aug 9, 2009, 10:21:00 PM8/9/09
to Firebug
Eddie does the tracing console show ERRORS? I'm guessing maybe
"charCode" errors?
jjb

Tom

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Aug 27, 2009, 3:20:26 AM8/27/09
to Firebug
I am also getting horribly slow performances with firebug since 1.4
just take seconds sometime to switch tabs I have the feeling that DOM
tab is the root of the problem but I might be wrong. I am running
Windows 2008 and Firefox 3.013. Is the only solution to have
acceptable performances to downgrade to 1.3 which was working fine ? :
(

On Aug 10, 4:21 am, johnjbarton <johnjbar...@johnjbarton.com> wrote:
> Eddie does the tracing console show ERRORS? I'm guessing maybe
> "charCode" errors?
> jjb
>
> On Aug 9, 11:10 am, Ed Abrams <zeroaltit...@gmail.com> wrote:
>
> > So far, with the tracing version, I have been able to reproduce the
> > problem and make my mac go crazy on the fans (CPU maxed out), but I
> > have not yet thrown the stop script exception that will give the line
> > number.  I'll keep trying.  It would be helpful to know whether other
> > people with the same platform can reproduce this.
>
> > -Eddie
>
> > On Aug 5, 2:08 pm, johnjbarton <johnjbar...@johnjbarton.com> wrote:
>
> > > Eddie, please install Firebug1.4X.2, open the tracing window with
> > > > > I am also getting extremely slowperformancewith Firebug1.4.x on FF
> > > > > 3.0.  Firebug 1.3.3 did not have this issue.  I disabled all other
> > > > > plug-ins, but that did not help.  Then, I tested it on a new profile,
> > > > > and that did not help either.  Firebug is tooslowto be usable at

johnjbarton

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Aug 27, 2009, 11:45:39 AM8/27/09
to Firebug
Without a test case there is not a single thing we can do about this
problem.
jjb

Pierre Bertet

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Sep 3, 2009, 1:06:37 PM9/3/09
to Firebug
I am encountering the same performance issue since version 1.4 (OS X
10.5 and Windows XP SP2): when Firebug is on, Firefox becomes really,
really slow.

On 27 août, 17:45, johnjbarton <johnjbar...@johnjbarton.com> wrote:
> Without a test case there is not a single thing we can do about this
> problem.
> jjb
>
> On Aug 27, 12:20 am, Tom <supp...@dataillusion.com> wrote:
>
> > I am also getting horriblyslowperformances with firebug since 1.4

Jan Odvarko

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Sep 4, 2009, 2:49:47 AM9/4/09
to Firebug
I would be curious if Firebug 1.5a23 solves these performance
problems.
http://getfirebug.com/releases/firebug/1.5X/firebug-1.5X.0a23.xpi

We have made some performance optimization based on some fixed Firefox
bugs.
Honza

Pierre Bertet

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Sep 4, 2009, 5:20:11 AM9/4/09
to Firebug
This is the version I am already using (1.5X.0a23).

On 4 sep, 08:49, Jan Odvarko <odva...@gmail.com> wrote:
> I would be curious if Firebug 1.5a23 solves these performance
> problems.http://getfirebug.com/releases/firebug/1.5X/firebug-1.5X.0a23.xpi

johnjbarton

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Sep 8, 2009, 1:41:22 PM9/8/09
to Firebug


On Sep 4, 2:20 am, Pierre Bertet <pierre6...@gmail.com> wrote:
> This is the version I am already using (1.5X.0a23).
>

In that case we need a new test case: http://code.google.com/p/fbug/issues/list
jjb

Pierre Bertet

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Oct 15, 2009, 5:49:47 PM10/15/09
to Firebug
javascript.options.strict was set on "true"... Fixed :-)
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