541932 - Huge Memory allocation if I open serveral Links in a new tab

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[Manuel Koenig]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; de; rv:1.9.2) Gecko/20100115 Firefox/3.6 (.NET CLR 3.5.30729)
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; de; rv:1.9.2) Gecko/20100115 Firefox/3.6 (.NET CLR 3.5.30729)

If i open some links (up to 20) in a new tab using the context menu for example on Google News or YouTube, Firefox allocates a huge amount of memory and never set it free again.
I have to close and reopen firefox to set the memory free again.

Reproducible: Always

Steps to Reproduce:
1. Start Firefox (V3.6 or below)
2. Goto YouTube and search for some things which return some results
3. Open some of the results in a new tab so that you have circa 15 Tabs
4. Watch the Memoryallocation with the Windows Taskmanager while you are doing this



This Problem exists not only on Windows XP. It's also available on Vista SP2 and Windows 7 32/64bit.

Comment 1

[Jo Hermans]

every Youtube page uses Flash - and that uses a *lot* of memory

Comment 2

[Manuel Koenig]

I know that Flash uses a *lot* of memory.
But I expect, if I close a tab that the memory which was used by this tab is set free. But this never happens.

There must be a way to do this because some systems only have 2GB of Ram and if Firefox gathers 1.5GB of it you've got a problem.

Comment 3

[Jo Hermans]

see bug 501485 comment 2 : for performance reasons, Firefox is not unloading plugins anymore when you move off the page. Bug 501485 is for investigating a way to negotiate with the plugin when an appropriate unload time would be. There's an automatic unload when you set plugins.unloadASAP to true in about:config, but it's buggy.

Note that it's not a leak : a new page with Flash would not need to allocate some memory and re-init the plugin, because it's already there. On a website like Youtube, that's a big speed improvement. On the other hand, there are also leaks inside Flash itself, see for instance bug 537154.

I guess that if you open 20 pages with Flash, it consumes a lot of memory to hold all 20 Flash objects together. And if you close all 20 pages, that memory would remain allocated, waiting for you to open *another* 20 pages. If you would open the pages one by one, you would see less memory in use.

Developers: wouldn't it be time to investigate the unload strategy again ? Many people might consider this a memory leak, even when it isn't in the strict sense. I guess this might fit in the Electrolysis project (bug 501485), because it might also free up the mozilla-runtime.exe process.

Comment 4

[Marco Castelluccio [:marco]]

Marking as RESOLVED INCOMPLETE, because this bug is duplicate of other bugs and because it doesn't contain useful informations.