263205 - Download Manager pegs 1Ghz CPU at 90% for 45 seconds to download a file

Status: RESOLVED DUPLICATE of bug 161783

(Toolkit :: Downloads API, defect)

Description

[Eric Johnson]

User-Agent:       Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; rv:1.7.3) Gecko/20040913 Firefox/0.10.1
Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; rv:1.7.3) Gecko/20040913 Firefox/0.10.1

Running Firefox 0.10.1 on a PowerBook G4 w/1 Ghz CPU & 1GB RAM.  Mac OS X
10.3.5, Java 1.4.2 update 2.

When I download a large file (like a 3 MB PDF), it takes a long time for the
download manager to start and execute the task.  During this time, the system
CPU goes to 90% and remains there until the download is complete and the
download manager quits.

If this is expected startup overhead for invoking a download manager that hasn't
been instantiated, I'd suggest offering the user the option of instantiating the
download manager on Firefox startup and not each time the user downloads a file.

Reproducible: Always
Steps to Reproduce:
1.  Download any large file using the above setup.
2.
3.

Actual Results:  
System CPU goes to 90% while the download manager is running.

Expected Results:  
Consume a reasonable amount of CPU

Comment 1

[Eric Johnson]

Attachment: Activity Monitor trace of Firefox PID while DL manager cranking up CPU

Seems to show the JVM getting instantiated.  If so, this is alot of overhead to
go through each time a user needs to download something.

Comment 2

[Ryan Polk (Quark)]

*** This bug has been marked as a duplicate of 161783 ***

Comment 3

[:Gavin Sharp [email: [e-mail]]]

This does not seem like a dupe of that bug at all.