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Firefox for Android - heavy CPU load, slow page rendering

  • 8 respostas
  • 24 have this problem
  • 6 views
  • Last reply by heyjoe

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Again, this is about an Android version. Clean install, version 27, no addons.

1. So the thing I'm complaining about is that clicking links and loading/rendering pages takes way too much time comparing to almost any other Android browser (Stock Android browser, Chrome, UC Browser, Sleipnir). Can I offer a test case? Try opening this page http://forum.xda-developers.com/index.php?tab=all in Firefox, and then in, let's say, Sleipnir. Sleipnir will just load the page from top to bottom for about 40 seconds and then just stay idle, while Firefox will take several minutes to load the bottom of the page, but will NEVER stop and will just torture and torture the CPU.

2. Moreover, another test case. Set Firefox to restore last session. Open 11-13 tabs from maybe the same good old XDA forum, then kill Firefox from memory, then open again, and CPU load will hold on about 60% and never stop (maybe will, but I've been waiting for 10-15 minutes, and it didn't).

3. One more thing I want to ask, what does Firefox do when it is in background? I can open just a couple of pages, then minimize FF and go to task manager (Android Tuner) and there I can see how FF continuously consumes 2-8% of CPU. In fact all android browsers does the more or less the same, but as a big fan of desktop Firefox, I'd like the Firefox for Android would also be the best.

Thanks in advance Your loyal follower

Again, this is about an Android version. Clean install, version 27, no addons. 1. So the thing I'm complaining about is that clicking links and loading/rendering pages takes way too much time comparing to almost any other Android browser (Stock Android browser, Chrome, UC Browser, Sleipnir). Can I offer a test case? Try opening this page http://forum.xda-developers.com/index.php?tab=all in Firefox, and then in, let's say, Sleipnir. Sleipnir will just load the page from top to bottom for about 40 seconds and then just stay idle, while Firefox will take several minutes to load the bottom of the page, but will NEVER stop and will just torture and torture the CPU. 2. Moreover, another test case. Set Firefox to restore last session. Open 11-13 tabs from maybe the same good old XDA forum, then kill Firefox from memory, then open again, and CPU load will hold on about 60% and never stop (maybe will, but I've been waiting for 10-15 minutes, and it didn't). 3. One more thing I want to ask, what does Firefox do when it is in background? I can open just a couple of pages, then minimize FF and go to task manager (Android Tuner) and there I can see how FF continuously consumes 2-8% of CPU. In fact all android browsers does the more or less the same, but as a big fan of desktop Firefox, I'd like the Firefox for Android would also be the best. Thanks in advance Your loyal follower

All Replies (8)

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Looks like Google Ads javascript is causing most of the delay. I opened a bug for the issue, though most likely it would require Google to fix their Ad code. This is likely the cause of your issue 1 and 2.

https://bugzilla.mozilla.org/show_bug.cgi?id=970072

JS and such can poll in the background which can cause a low but constant cpu useage.

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As a matter of fact, I could reproduce number 2 even with JS disabled.

Today I've installed Dolphin and need to say, it opens that XDA's main page in maybe 20 seconds without any issue.

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Number 3: What does firefox do in the background? FF for desktop had a memory leak that was fixed in the last update to improve performance. It happened mostly when leaving tabs open for a few days. In FF for android you can troubleshoot the cached data that firefox is using from the App Manager in the Android Settings. If you clear the data stored, this may wipe history and data the application has to customize the experience, but may reduce memory consumption on the android device.

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Sorry, but I don't see how is this related to my question, I was talking about the real-time CPU load and not memory consumption that can bee seen in several days.

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Hi there HeyJoe!!! This is DaveCMozilla. I'm sorry to hear about your unfortunate experience with Firefox. If I am reading your situation right, I'm interpreting that Firefox seems to be consuming more data than it should consume. I have to be honest, from reading your issue it's hard to cipher whether this is your mobile phone this is happening to or your own PC. If this is the Firefox browser, for Android devices, then try performing these steps:

1.) Tap the Menu button (either at the bottom edge of the screen or in the the top-right corner) and select Settings (you may need to tap More first) .

2.) Tap Privacy and choose Clear private data.

3.) Select the items you want to clear and then tap Clear data.

(https://support.mozilla.org/en-US/kb/how-do-i-clear-private-data-firefox-android)

This will erase the access files and will wipe out information on sites you have been to. After trying these steps, try opening Firefox, on your mobile device, and go to any webpage to see if it opens up faster. The only other thing I can recommend is that you might want to consult your mobile service provider to see which type of data speed service that your service provider has you using. I know the 2 main types of data speeds are 3G and 4G. Here are some links that will provide more information on the different data speeds:

(http://en.wikipedia.org/wiki/3G)

(http://en.wikipedia.org/wiki/4G)

I would recommend looking into the clearing of the access "junk files" and the access private data on you phone first. I would also definitely consult your mobile service provider about the type of data service you have with them as well. If your plan is suppose to have "4G" data service with it, then you might want to consult your mobile service provider about that. However, not all areas are capable of having these "4G" data speeds. The type of speeds can switch from time to time as you never know what type of tower your cell phone might pick up. Also be aware that the more users, using the same data as you on the same tower, the less speed you are going to have. This is all I have for now. I will try to conduct some research and if I find out anything new I will get back to you as soon as possible. Also, if there is any additional information you could provide for me, that will also help me resolve your issue of Firefox being so slow when loading a page.

davecmozilla modificouno o

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Guys, are you sure you've been reading MY post? Dear DaveCMozilla, I've tried to search a word "data" in my post and couldn't find a single instance of such. But the title says "Firefox for Android...". Are you sure we are talking about the same post?

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Ah, that makes more sense. heyjoe, did kbrosnen's post with the related bug look like your issue?

I have found a work around that was useful back in version 22. In the about:config there is a preference that controls disk cache maximum. Check out the solution to see if this improves the performance https://support.mozilla.org/en-US/que.../947996

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Thank you for your response, but I tried to play with caches and it doesn't help. Moreover, I have 16GB of internal storage and never seen a "Low disk space" warning on this device.

kbrosnen was talking about a heavy Goggle's JS file an on some part he is right, but it's only a half of problem, 'cause CPU load persists at level 50-60% even with JS disabled in FF. And again, it's only FF's problem, Dolphin browser doesn't have that problem at all.