46738 - nsStr usage is excessive

Status: RESOLVED DUPLICATE of bug 46892

(Core :: XPCOM, defect, P3)

Description

[Doug Turner (:dougt)]

I have been poking around with string usage this yesterday morning.  I hacked up 
nsStr a bit to produce the stats on the number of times the same string is 
deleted.   I changed it so that I only know about strings that are deleted. 

Attached are some tab delimited files that include the string used, the number 
of times deleted, char count and a bloat number (char
count * num times deleted).  It is interesting to see what boils to the top.  

There is alot that we can clean up here. 

a.txt includes what it takes to startup winEmbed.exe, a simple embedding 
application, and browse to http://people.netscape.com/dougt. 

b.txt I load bonsai.mozilla.org after the people page.

Comment 1

[Doug Turner (:dougt)]

Attachment: a.txt

Comment 2

[Doug Turner (:dougt)]

Attachment: b.txt

Comment 3

[Scott Collins]

Copied the attachments over to bug #28221, and made some comments there.  I think 
this bug may be completely covered by that one.  I'm tempted to mark it as a 
duplicated.  Doug: what conclusions do you draw from this data?  I pose this 
question in the other bug ... if you agree this bug is a duplicate (or at least a 
subset) then you should answer it there.  Then we'll mark this bug a duplicate.  
Alternatively, you may consider this bug a blocker for 28221 (which is one 
interpretation of a sub-bug).

What problem, exactly, does this demonstrate?  Too many instances of what turns 
out to be the same string?  I think we need more information before we can know 
how to remedy the problem.  For instance, repeatedly making the same string key 
from constant data can be fixed with an |nsSharedString|.  But repeatedly parsing 
strings that happen to be equal, e.g., "href=", might not be fixable.

Comment 4

[lchiang]

per email with Jud, changing nsbeta3+ to nsbeta3- on all "embed" keyword bugs
since embedding changes will not be made in the mn6 branch. If you feel this bug
fix needs to go into mn6 branch, please list the reasons/user impact/risk and
nominate for rtm. Thanks.

Comment 5

[Scott Collins]

|nsStr| must die, as noted in bug #46892.  So this bug is really a duplicate.

*** This bug has been marked as a duplicate of 46892 ***