Re: Yanick Belanger makes NIST-SIP burn tires.

Jeroen,

Yes indeed, Yanick pointed me at that too. It turns out that with TCP 
transport, I can get 169 CAPS.  Also measuring instantaneous thruput, 
the thruput is higher at the start of the test using UDP but degrades 
thereafter. Therefore, there is an issue with flow control using UDP. I 
have been toying with some ideas but all of them involve sleep. Do you 
know any layers on top of UDP that can implement flow control in java ? 
One idea I had was to look at the client transaction table size and 
sleep if the size exceeds threshold. Blocking the caller in 
SipProviderImpl is not very nice because it could be called from within 
a listener and if your listener is not re-entrant, you might get into a 
deadlock.

Any ideas? I am committing a version of the test that allows you to 
easily switch between transports and try things out. The problem boils 
down to finding a cheap and good flow control algorithm for UDP. 
Pointers would be appreciated.

Regards

Ranga


Jeroen van Bemmel wrote:

> Ranga,
>
> CPU usage stays below 100% because there is a call to sleep(5) in 
> Shootist. If you remove that you get 100%, but calls start failing. It 
> should not be necessary to sleep in order to avoid failing calls, this 
> is something that needs to be fixed
>
> Regards,
> Jeroen
>
> M. Rangnathan wrote:
>
>> Folks,
>>
>> If you are writing a performance sensitive application (i.e. Server
>> application), this will be of interest to you. Yanick Belanger has
>> made several improvements on the code lately that have improved the
>> performance by at least 10%. Do download and try it out in your
>> application and let us know how these changes improved your
>> application. There still seems to be low cpu usage on self test. If
>> there's a profiling whiz out there, maybe you can let us know whats
>> blocking the cpu. The test to run is src/test/load/concurrency
>>
>> I just love it when people get my code to run faster. Learn something
>> new all the time.
>>
>> Thanks to Yanick on behalf of the community. Good stuff.
>>
>> Hack on!
>>
>> Ranga. 
>
>
>


-- 
M. Ranganathan 

Advanced Networking Technologies Division,
National Institute of Standards and Technology (NIST),
100 Bureau Drive, Stop 8920, Gaithersburg, MD 20899. 
tel:301 975 3664 , fax:301 590 0932 http://w3.antd.nist.gov/
Advanced Networking Technologies For the People!