[armedbear-devel] Profiling ABCL exception handling

[Erik Huelsmann]

Hi Joel,

>> Running an exception profile on Maxima running its test suite shows
>> lots of non-local transfer of control exceptions: Return, Go and
>> Throw: during a run of ca 10 minutes, I'm finding 5.5 million
>> exceptions being thrown which - as MissionControl calculated for me -
>> should mean an average of little over 12k/s. I guess that's kind of
>> expected with our strategy for non-local transfers of control.
>
> To put this into context we (developers at JRockit) expect ~1000
> exceptions / core / sec from a "typical" Weblogic app. We define this
> as a bit much but not terribly excessive.
>
> My guess is that between the horrible support for fixnums (and the
> really slow bignums) in Java and the order of magnitude higher
> exception count this will dominate your performance.

Does the exception count include all "rethrow"s which are part of the
"finally" processing? If all "athrow" instructions are being counted,
I think we can do better, if we think this through really well.


Regards,


Erik.