28842 - instrument nsString allocation/copy code to find degenerate users

Status: VERIFIED DUPLICATE of bug 28221

(Core :: XPCOM, defect, P3)

Description

[Chris Waterson]

Use XPCOM stack walking code to instrument nsString::Append(), 
nsString::Insert() et al. to identify places that lead to degenerate use of 
nsString. By "degenerate", I mean code that causes excessive allocation or bulk 
moving of memory.

Comment 1

[Scott Collins]

From my comment on the related bug

  <http://bugzilla.mozilla.org/show_bug.cgi?id=28841>

"A good measure might be to add (for profiling only, of course) a time field to 
the string structure, and log how _long_ a string exists at a certain size.  That 
way we could tell the difference [e.g.] between having lots of empty strings and 
having lots of strings that just happen to start empty but don't really spend 
much time in that state."

Comment 2

[Scott Collins]

This data will also help me do the right thing on Bug 26435.

Comment 3

[Chris Waterson]

this work is being done under bug 28221.

*** This bug has been marked as a duplicate of 28221 ***

Comment 4

[leger]

Marking Verified as a dup