Re: interest in minor contention issues?

[Jonathan Ellis <jb...@gmail.com>]

Hi Jason,

Thanks for looking into this!

What tool are you using?  I belatedly noticed your tickets (we should
have them resolved for 0.6.9) and it might be useful to do another
check against the 0.7 code.

On Fri, Aug 6, 2010 at 3:25 PM, Jason Fager <jf...@gmail.com> wrote:
> Hi all,
>
> I'm doing some work with the Java Debugger Interface, and I'm using
> Cassandra as a test bed.  I've found a few minor contention spots
> (example: MessageDigest.getInstance() being called for every
> invocation of FBUtilities.hash()), but before I start possibly
> spamming your jira with them, I wanted to gauge the general interest
> in knowing these kinds of minor issues.  I'm happy to report them as
> they come up while I'm doing my work, but if you consider them too
> minor to worry about until they actually show up as impacting
> performance during profiling, I don't want to annoy anyone.  Let me
> know.
>
> - Jason
>



-- 
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com

Re: interest in minor contention issues?

[Jason Fager <jf...@gmail.com>]

Hi Jonathan,

No problem, thanks for all the work you and everyone on the dev team
do on Cassandra.

I have a small bit of wrapper code for scripting the Java Debugger
Interface, which is up at https://github.com/jfager/jdiscript.  I also
have a short writeup on it at
http://jasonfager.com/888-introducing-jdiscript/.  In a nutshell, I
just ran Cassandra with the debugger set to fire  events on JDI's
MonitorContendedEnterEvent, and handle them by printing out
stacktraces.

If I get some time in the next day or so, I'll take another shot at
the 0.7 codebase.

Best,
Jason



On Tue, Dec 28, 2010 at 3:14 PM, Jonathan Ellis <jb...@gmail.com> wrote:
> Hi Jason,
>
> Thanks for looking into this!
>
> What tool are you using?  I belatedly noticed your tickets (we should
> have them resolved for 0.6.9) and it might be useful to do another
> check against the 0.7 code.
>
> On Fri, Aug 6, 2010 at 3:25 PM, Jason Fager <jf...@gmail.com> wrote:
>> Hi all,
>>
>> I'm doing some work with the Java Debugger Interface, and I'm using
>> Cassandra as a test bed.  I've found a few minor contention spots
>> (example: MessageDigest.getInstance() being called for every
>> invocation of FBUtilities.hash()), but before I start possibly
>> spamming your jira with them, I wanted to gauge the general interest
>> in knowing these kinds of minor issues.  I'm happy to report them as
>> they come up while I'm doing my work, but if you consider them too
>> minor to worry about until they actually show up as impacting
>> performance during profiling, I don't want to annoy anyone.  Let me
>> know.
>>
>> - Jason
>>
>
>
>
> --
> Jonathan Ellis
> Project Chair, Apache Cassandra
> co-founder of Riptano, the source for professional Cassandra support
> http://riptano.com
>