481260 - JIT stats in tracemonkey can interfere with stdout-using embeddings

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Wesley W. Garland]

Attachment: Disable output of JIT stats recorder except when TRACEMONKEY=verbose

During shutdown of the JS interpreter, if the JIT engine has been called it outputs statistics about its use in the js_FinishJIT() function in jstracer.cpp.

This output cannot be disabled without either disabling JIT, or compiling a non-DEBUG build. 

This is not acceptable for embedders using JavaScript to generate stdout output, such as CGI scripts, programs which feed shell pipelines, etc.

I have attached a patch which prevents the stats from outputting except when the TRACEMONKEY=verbose environment variable is set, by checking the js_verboseDebug global variable.

Comment 1

[Jason Orendorff [:jorendorff]]

Comment on attachment 365272 [details] [diff] [review]
Disable output of JIT stats recorder except when TRACEMONKEY=verbose

I will push it tonight if nobody beats me to it.

Comment 2

[Andreas Gal :gal]

Comment on attachment 365272 [details] [diff] [review]
Disable output of JIT stats recorder except when TRACEMONKEY=verbose

The brief summary is pretty useful for debugging with the shell without having to endure the full-on spew. Could we maybe introduce another TRACEMONKEY= parameter? Like TRACEMONKEY=summary or something?

Comment 3

[Andreas Gal :gal]

Attachment: v2

Comment 4

[Jason Orendorff [:jorendorff]]

I pushed Wes's version before I saw Gal's comment.  So I pushed Gal's version too.

http://hg.mozilla.org/tracemonkey/rev/94d3afad4d2a
http://hg.mozilla.org/tracemonkey/rev/36ad79c019d8

Comment 5

[Robert Sayre]

http://hg.mozilla.org/mozilla-central/rev/36ad79c019d8

Comment 6

[Robert Sayre]

http://hg.mozilla.org/releases/mozilla-1.9.1/rev/abd16059e04f