Re: [OpenSTA-users] Performance testing with Open STA

[Bernie V. <Ber...@iP...>]

>>aim is to identify the number of orders created in an hour by 10 users.
>>Any ideas why I am getting these timeout errors?

< Michael wrote>

> Let's assume you have recorded and modeled your scripts correctly.
>
> Now, you are testing your server performance (throughput) by identifying
> the number of orders created in an hour by 10 users, right?
>
> Aren't you then looking for at what point the load would cause your
> server to timing out request?  And bingo, you have reached that point.

Michael,

I understand what you are saying in principle and I don't disagree. When 
looking for bottlenecks, a useful technique is to compare throughput vs. 
load and see when it becomes non-linear. Frequent timeouts will always lead 
to non-linear throughput vs. load (users) graphs.

> Aren't you then looking for at what point the load would cause your
> server to timing out request?  And bingo, you have reached that point.

If I understand Chris' email, Chris has found the point where OpenSTA times 
out, not the application. I have no idea how long Chris' single user 
response times are. If they are just a few seconds, then given the default 1 
minute timeout (actually, the default value is 1 minute but OpenSTA can take 
anywhere up to 2X the timeout value to actually deliver the timeout error to 
scripts.) the server(s) have reached a significant bottleneck. If single 
user response times started at close to 1 minute, then a response time of 
1.5 minutes would not be that unusual or indicate a bottleneck under load.

-Bernie
(www.iPerformax.com)