409821 - 2% Tdhtml regression on boxset (CmTrunk) following bug 409109

Status: RESOLVED FIXED

(Camino Graveyard :: General, defect)

Description

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

There's a clear 2% Tdhtml regression on boxset following the checkin for bug 409109; we'd been relatively stable near 900ms for the last week or so, and the first build following the checkin for bug 409109 jumped to 920ms, where we've remained ever since.

It's hard to tell if any other box experienced this regression; they seem either jumpier in general or prone to wild swings several cycles a day.  You maybe could see something on bl-bldlnx03_fx-linux-tbox-head for the first few cycles after the checkin, but then it resumed its usual swings.

Comment 1

[Igor Bukanov]

(In reply to comment #0)
> There's a clear 2% Tdhtml regression on boxset following the checkin for bug 409109; 

This is rather interesting especially given that the check in for bug 364776 have not affected Tdhtml timing. That bug added a new functionality to the JS engine without changing DOM to use the new API. Given that the older functionality of the JS engine was implemented on top of the new API, I would expect any slow down to happen after the check in bug 364776. 

Bug 409109 switched DOM/XPConnect to the new API and should make particular methods to be called significantly less frequently. Tomorrow I will try to revert the check in for bug 409109 to see what is wrong. 

Comment 2

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

When Jesse backed out bug 364776 and bug 409109, boxset dropped right back to 900ms.

Comment 3

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

Igor, Tdhtml on boxset has come back up to the 920/925ms range and remained (with one exception) up there following your re-checkin of bug 409109.

Comment 4

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

The third checkin for bug 409109 seems to have no significant effect on boxset's Tdhtml; marking this FIXED.