551728 - Update MMgc documentation with blacklist debugging info

Status: RESOLVED FIXED

(Tamarin Graveyard :: Garbage Collection (mmGC), defect, P3)

Description

[Mike Morearty]

https://developer.mozilla.org/en/MMgc needs some updates: We need to add description of blacklist debugging technique (GC::addToBlacklist() etc.)

I tried the GC::WhosPointingAtMe() function that is described in https://developer.mozilla.org/en/MMgc#Allocation_traces.2c_deletion_traces_etc. , but it caused an assertion.  Tommy says it may not work any more, and that I should use the newer blacklist stuff; but it is not documented on the wiki or in the code.

Comment 1

[Mike Morearty]

This changeset describes what I think it needs to say:

changeset:   3039:30e3807a2100
user:        Tommy Reilly <[e-mail]>
date:        Tue Nov 10 10:39:46 2009 -0500
files:       MMgc/FixedAlloc.cpp MMgc/FixedAlloc.h MMgc/GC.cpp MMgc/GC.h MMgc/GCHeap.cpp MMgc/GCHeap
description:
New blacklist facility.  Use GC::addToBlacklist to put something on
the list and then when a Sweep happens we print out the back pointer
chain if the thing is still around.  (r=lhansen)

Comment 2

[Mike Morearty]

Doing that works in that it prints out a series of hex addresses, but then I'm not sure what to do with those hex addresses.

Comment 3

[Tommy Reilly]

Attachment: Somethings better than nothing...

Comment 4

[Lars T Hansen]

Comment on attachment 504526 [details] [diff] [review]
Somethings better than nothing...

Indeed.  I have an index.html pending, I'll make sure to link this one into it.

Comment 5

[Tommy Reilly]

http://hg.mozilla.org/tamarin-redux/rev/10f69eb4d818

Comment 6

[Steven Johnson]

Comment on attachment 504526 [details] [diff] [review]
Somethings better than nothing...

Good start. Other stuff I've noted:

-- AVMFEATURE_MEMORY_PROFILER seems to need enabling.
-- for mac, uncomment startAtosProcess in MacPortMMgc