669404 - browser consumes 500mb with only one tab loaded

Status: NEW

(Firefox :: Tabbed Browser, defect)

Description

[juan becerra [:juanb]]

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:7.0a1) Gecko/20110705 Firefox/7.0a1

Since I can remember I've noticed my browser take up about 800mb of memory, even though I have it setup so that it only loads one tab on restart (load tabs on demand). After disabling all extensions, and restarting with three windows open, only one tab loaded in each, memory consumption still hovers around 500mb.

I have a gazillion (300) tabs, again, only three of them open at a time. For other people, the memory consumption is not as high with about 100 tabs open.

Comment 1

[Henrik Skupin [:whimboo][⌚️UTC+2]]

Juan, how large is your sessionstore.js file?

Comment 2

[Justin Dolske [:Dolske]]

What's about:memory say?

Comment 3

[juan becerra [:juanb]]

Attachment: about:memory after restarting

Also, sessionstore.js is 2.3mb - How much memory overhead is there per tab restored, but not loaded?

Comment 4

[Randell Jesup [:jesup] (needinfo me)]

Quite a bit of overhead, actually - it loads the session history and a bunch of other things.  I assume you're using max_concurrent_tabs=0 (not BarTab, which hasn't been updated); max_concurrent_tabs loads more than BarTab does I understand.

2.3MB sessionstore for 300+ tabs is actually good.

It would be good to look at what else we can defer when restoring non-loaded tabs, but it's not an exposed UI option - though BarTab or equivalent extensions likely will make it easy to get again.