Memory leak on Firefox only

riwang

Hi there,

I'm running Lightstreamer to push high-frequency data, which is updated per second, to browsers. I'm using the LS Javascript library to get the messages from the LS server.

To measure the browser memory usage, I ran my web page in Firefox 3(FF3) and IE7 for a few hours. I noticed the commit memory for IE7 was quite stable over the time. But the commit memory for FF3 has been increasing throughout. The Resource Monitor on Vista showed FF3 incremented about 100KB memory per second. If I stopped the Lightstreamer server, hence there is no message to the browser, the memory increase also stopped.

To isolate the issue, I turned off other javascript code. I also commented out "pushTable.onItemUpdate = myUpdateItem;" so that there is no handler to process the LS messages. But FF3 continues to increment the memory consumption as messages are pushed from the server.

Here are some memory data I collected for FF3 and IE7. It seems IE7 is doing OK.

Right after opening the webpage: 130MB(FF3) 142MB(IE7)
Running for 2 hour 40 mins: 255MB(FF3) 148MB(IE7)
Running for 3 hour 20 mins: 273MB(FF3) 148MB(IE7)

Can anyone please advise?

Thanks,
Richard

Alessandro Alinone

Hi Richard,

Do you have Firebug installed? It is usually the cause of growing memory. If you have it, try told completely disable it (not just suspend it).
Please let us know.

Cheers,
Alessandro

riwang

Hi Alessandro,

I disabled Firebug, but I was still seeing the memory increase in Firefox.

I'll try to remove Firebug completely, then re-do my memory measurement. I'll report back soon.

Thanks for your help.

Richard

Alessandro Alinone

Hi Richard,

We did a new test with a freshly installed Firefox 3. I confirm we cannot observe any permanent memory growth.
Do you nave any news on your side?

Thanks, cheers,

Alessandro

riwang

Hi Alessandro,

Thanks for your follow up. We've been very busy in the past month trying to implement some new features. Sorry for replying back late.

I still observe memory issue, but it's hard to isolate which part of the Javascript code is causing it since our app is quite complex. Nonetheless, it's very reassuring to know that your test confirms there is no permanent memory leak in FF3. Our app is moving towards the "one-page" model, therefore even "pseudo" memory leaks, which require user to reload the web page to reclaim memory, should best be avoided. Do you observe such "pseudo" memory leaks in FF or IE?

Regards,
Richard

Alessandro Alinone

Hi Richard,

No pseudo-memory leaks due to Lightstreamer have been observed on FF or IE. In our tests, we have kept a streaming page open for days, without any reloads, and no memory growth has been observed on both IE and FF.

Cheers,
Alessandro

riwang

Hi Alessandro,

That's good to know. Thanks so much.

Richard

riwang

Hi Alessandro,

We are still seeing severe memory issue with our web app. If we left our app running for 24 hours, the browser (FF and IE) memory usage goes up to 1.2 GB.

To debug the memory issue, I made a few simplification to our app.

1. The LS server pushes out 200K data per second. This exacerbates the memory issue and make it more visible quicker.
2. The web app only receives the data, but not consume the data. I set table.onItemUpdate to an empty function that does nothing. This eliminates the possibility of other parts of the web app keeping references to the streamed data.

After running Firefox 3 for 30 minutes, the browser memory usage goes from 300MB to 700MB. I do have Firebug installed on the Firefox. I'm going to try IE to see how much memory it consumes.

Can you please help?

Thanks,
Richard

Alessandro Alinone

Hi Richard,

It is important to see what happens with that test case with Firebug disabled or on IE.
Please, let us know.

Also, may you provide us with your test code or environment, so that we can try to replicate it?

Cheers
Alessandro

riwang

Hi Alessandro,

My IE test shows that the browser memory does not increase over time. After I disabled Firebug, Firefox memory does not increase dramatically either.

It seems Firebug does cause serious memory leak on Firefox. I think I would show a popup to ask users to disable Firebug if the Javascript detects user's browser has Firebug installed.

Thanks,
Richard

Alessandro Alinone

Richard,

Thanks for confirming this.

In the next version of the Lightstreamer Web Client library, we will detect and warn about the presence of Firebug too.

Cheers,

Alessandro