713364 - very heavy disk access immediately after launch

Status: RESOLVED WORKSFORME

(Firefox :: General, defect)

Description

[Jay Howard]

User Agent: Mozilla/5.0 (Windows NT 5.1; rv:9.0.1) Gecko/20100101 Firefox/9.0.1
Build ID: 20111220165912

Steps to reproduce:

Launch Firefox.

OS was Windows XP SP 3. Hardware was an older single-core laptop with a slow 4200rpm disk drive.


Actual results:

After my home page (google.com) loaded, Firefox goes through an extended period of heavy disk access.  So much so that it is unusable for about 20 seconds.  Note this is after the home page loads.  It also never happened with Firefox 8.0.1, so it's either a regression of caused by some new functionality in Firefox 9.


Expected results:

There should not have been an extended period of heavy disk access.

Comment 1

[Jo Hermans]

That's probably the disk cache being cleaned - that happens when there was the previous Firefox has crashed, and the disk cache is corrupt.

Comment 2

[Jay Howard]

(In reply to Jo Hermans from comment #1)
> That's probably the disk cache being cleaned - that happens when there was
> the previous Firefox has crashed, and the disk cache is corrupt.

I periodically run CCleaner which (supposedly) cleans out the entire cache.  It's possible (probable) CCleaner is screwing something up, especially if the cache structure changed between FF8 and FF9.  Even so, should it take FF ~20 seconds to recover from an "improperly deleted yet still mostly empty" cache?

Comment 3

[Jo Hermans]

You'll see some heave disk I/O for a while (30 seconds for a 1GB cache would not be unreasonable). But it's done in the background, the browser should not be blocked.

Comment 4

[:aceman]

I often see this on linux too, but nowhere near 20 seconds (but I have fast machine). I think there is some history expiration or something like that just after start of Firefox. Or some other places/cache cleanup. But it is not cache deletion, Firefox does not crash every day (almost never).

I do not say the activity I describe blocks the browser UI. I can just notice it by disk activity and impact on the whole system.

Comment 5

[Jay Howard]

I verified that I see this behavior when launching Firefox even without having first run CCleaner.

It may be especially noticeable on my machine (with respect to the UI thread) because it's a fairly slow single-core processor.  Though, I ran Firefox 8 on the same machine and never noticed anything like this.  It's definitely a new behavior in Firefox 9.

Is is possible the cache is stuck in some "broken" state and that every time I start Firefox 9 it tries (unsuccessfully) to repair it?

Comment 6

[Wayne Mery (:wsmwk)]

Jay, do you still see this issue when using a current version?

Comment 7

[Jay Howard]

I do not. Though, I stopped using that Windows XP laptop years ago and Firefox has (obviously) changed drastically since then. Feel free to close.

Comment 8

[Wayne Mery (:wsmwk)]

Thanks for the update