639515 - Greasemonkey 0.9.1 causes memory leak on entering/exiting private browsing mode

Status: RESOLVED WORKSFORME

(Core :: General, defect)

Description

[Steve Scott (pxbugz)]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.16 (KHTML, like Gecko) Chrome/10.0.648.127 Safari/534.16
Build Identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b13pre) Gecko/20110303 Firefox/4.0b13pre

Using the mozmill endurance test ( http://etherpad.mozilla.com:9000/testday-110304-addons for instructions and downloads) greasemonkey 0.9.1 shows a large increase in memory, that is never released, during the private browsing portion of the test.

Reproducible: Always

Steps to Reproduce:
1. install mozmill test suite linked above
2. run test_endurance with greasemonkey as an addon
3. check dashboard
Actual Results:  
Dashboard run http://mozmill.blargon7.com/#/endurance/report/66e0fb6bd5645ddae0ee8e21d000e51b

Expected Results:  
Memory should be released after entering and exiting private browsing mode with the addon installed.

Comment 1

[Steve Scott (pxbugz)]

CAUTION: clicking the endurance report in the first comment may crash firefox!

A better link is forthcoming

Comment 2

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Confirmed based on our results. 

(In reply to comment #0)
> http://mozmill.blargon7.com/#/endurance/report/66e0fb6bd5645ddae0ee8e21d000e51b

Please don't click on that link unless you don't want to see your main Firefox instance be frozen. Use another instance/profile for it.

Next step would be to get some manual steps or an easy way to reproduce with the Mozmill IDE.

Comment 3

[Steve Scott (pxbugz)]

Here is a shorter 100 iteration run that should load ok

http://mozmill.blargon7.com/#/endurance/report/66e0fb6bd5645ddae0ee8e21d0011f14

Comment 4

[Steve Scott (pxbugz)]

Greasemonkey beta released today showing the same issue:

http://mozmill.blargon7.com/#/endurance/report/66e0fb6bd5645ddae0ee8e21d0013bf4

Comment 5

[Steve Scott (pxbugz)]

Attachment: Unusable Leak Gauge log

Attempt at getting a leak gauge log with greasemonkey installed causes an unusable log to be generated.

Comment 6

[Henrik Skupin [:whimboo][⌚️UTC+1]]

I can reproduce it with Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0b13pre) Gecko/20110310 Firefox/4.0b13pre ID:20110310030427

Steps:
1. Install GreaseMonkey
2. Enter Private Browsing mode
3. Leave Private Browsing mode
4. Repeat steps 2-3.

As you can see the memory consumption is raising constantly and memory never gets freed again.

Comment 7

[Henrik Skupin [:whimboo][⌚️UTC+1]]

It's less noticeable in Firefox 3.6. It's memory consumption also increases but keeps staying at 100MB on my box, while for 4.0 there is no upper limit yet.

Comment 8

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Looks like this has been regressed between Firefox 4 beta 12 and RC 1. I will do checks with nightly builds now to narrow down the range.

Comment 9

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Not sure if I'm doing that right, but the results from leak gauge don't show any leak:

Results of processing log leak.log :

Summary:
Leaked 0 out of 0 DOM Windows
Leaked 0 out of 865 documents
Leaked 0 out of 775 docshells
Leaked content nodes in 0 out of 877 documents

David, is there another good way to get more information about?

Comment 10

[Olli Pettay [:smaug][[e-mail]]]

Something else is then perhaps leaking. Some JS objects? Images in the cache? Elements?

Btw, has anyone checked whether we leak something on shutdown?

I could try to check that later today.

Comment 11

[Boris Zbarsky [:bzbarsky]]

Greasemonkey doesn't seem to observe the private browsing notifications, in case that matters.

Comment 12

[Henrik Skupin [:whimboo][⌚️UTC+1]]

(In reply to comment #11)
> Greasemonkey doesn't seem to observe the private browsing notifications, in
> case that matters.

Lets add some GreaseMonkey developers to get them involved.

Comment 13

[Anthony Lieuallen]

> Greasemonkey doesn't seem to observe the private browsing notifications, in
> case that matters.

That is correct.  But what might we do with them if we were?

Comment 14

[Boris Zbarsky [:bzbarsky]]

Nothing I can think of offhand.  The point was that this is not a leak due to your code doing something weird in response to the notifications, since your code doesn't observe the notifications.  ;)

Comment 15

[Steve Scott (pxbugz)]

No longer seeing this issue in latest nightlies with Gresemonkey 0.9.14

Comment 16

[Dave Hunt [:davehunt] [he/him] ⌚GMT]

I'm curious to know how you retested this. Do you have some reports that show the memory usage does not increase during the private browsing test?

Comment 17

[Steve Scott (pxbugz)]

(In reply to Dave Hunt (:davehunt) from comment #16)
> I'm curious to know how you retested this. Do you have some reports that
> show the memory usage does not increase during the private browsing test?

I only did this test by observing about:memory as I had tried test_endurance but it seems to get stuck on testAddons_OpenAndCloseExtensionList\test1.js with the current nightly and didn't feel up to digging around to disable the test.

There appears to be no increase in memory usage or zombie compartments so I thought to close it as there have been a few new versions of greasemonkey anyway.

If there's a way to disable that test or just run the private browsing one I can check properly and set to block Bug 700547 if necessary.