Thunderbird:Testing:Memory Usage Problems
The main purposes of this wiki page are to help users self diagnose their memory problems, and help triagers to help others, so that appropriate action can be taken.
High memory usage comes in several types, and there can be many causes. Some high memory situations are normal. Some are not and are therefore valid bugs.
It is useful to ask and answer the question "What is 'normal' memory usage?" There is no absolute answer, because usage varies depending on the user's environment (number of extensions loaded, number of folders and accounts, etc). However, broadly speaking, you probably should not see sustained memory usage over 150MB, and definitely not above 200MB. If you are not using more than 150MB then there is a fair chance you are not seeing a major problem.
The big groupings that make up the worst causes include:
- extensions
- OS files not being closed after Thunderbird is done using a folder (internally called a db, or database)
- large folders with high delete activity that aren't compacted occassionally, or where compact was not successful (eg. bug nnn)
- moving large numbers of messages via drag and drop
Things which increase memory usage, but aren't "problems", or don't rise to the level of major problems:
- virtual folders
- extensions
- extremely large folders
- 'Memory leaks'. Most people have heard the term 'Memory leaks'. The classic memory leak is a program not releasing some temporarily used memory. Certainly Thunderbird has small leaks, but none that we know of that are large enough to cause perceptible performance problems.
Diagnosis:
- Start Thunderbird in Safe Mode. If problem is not seen, determine which extension is causing the problem and contact the author. Otherwise, continue ...
- Does the problem involve newsgroups? See these bugs (_bug query_). If not one of these problems, continue ...
- Does problem resolve by disabling indexing (unlikely but work checking)? Disable at Tools|Options|Advanced|General and restart Thunderbird. If the problem goes away, please file a bug. Otherwise, continue ... (and re-enable indexing now, or later)
- If there is reason to suspect folders (db) are not being closed - file a bug and attach a db log
- set up db logging using MSGDB:5 (gets you all) or MSGDB:1 (gets you the open and close actions) using logging instructions
- use tryserver build appropriate to your platform that includes 010-01-14_08:10-bienvenu@nventure.com-1263484981/bienvenu@nventure.com-1263484981-mail-try in the name
- https://bugzilla.mozilla.org/enter_bug.cgi?product=Thunderbird&format=guided File a bug] and state that you have a msgdb log in the comments.
- x
Related bugs and references:
Fixed bugs in version 3 (most recent at top):