[thelist] load testing tools and concurrency

[John DeStefano]

Hi all,

I've been asked to look into why a particular web application is  
responding very slowly, and come up with a sound method for testing  
the server.  I tried hammering it with Apache's AB, which seems like a  
nice tool, but it returned inconsistent results, and I've read  
multiple reports of this being a problem.  cURL is another option.   
But I'm wondering whether there already exists some testing "suite"  
that would ease the entire process, by:
- generating a "real-world" load with each request, returning the  
entire contents of a page
- allowing both sequential and concurrent requests
- getting cached or non-cached results (by including a no-cache header  
with the request)
- record the results (avg,min,max,timeouts)
- graphing would be nice ;)
- and of course, it would have to be open-source, and Mac and/or Linux- 
based

Now that I'm finished dreaming, I'd appreciate your suggestions on  
something that covers any or all of these bases.


Now, as sidebar: this particular application (which was built using  
MySQL + Python + Apache) seems slow with sequential reads, but even  
worse when concurrent requests are used.  I'm being told that this  
isn't possible, since the server should be able to queue requests as  
they come in, sequential or otherwise.  While that seems evident,  
sequential reads return results, while concurrent reads (in any  
quantity: 10, 5, even 2) result in time-outs much more often.  Any  
thoughts on this?


Thanks,
~John