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From: Marc Slemko marcs@znep.com
To: Java Apache Users java-apache-users@list.working-dogs.com
Subject: Re: ab seems to be making extra requests while testing servlets
Date: Fri, Oct 8, 1999, 9:25 AM

On Fri, 8 Oct 1999, Kevin Macclay wrote:

> We're using ApacheBenchmark 1.3a and encountering a rather strange
> occurance.  We understand that the following call to ab means that ab will
> simulate 5 concurrent users each making 10 requests for a total of 50
> requests.
> 
> ab -n 50 -c 5 "http://www.oursite.com/servlet/OurServlet"
> 
> The strange thing is that our servlet gets called 55 times -- five extra
> times more than it should.  Is this an ab bug?  We're able to measure the

In this case, ab will make a maximum of 5 simultaneous connections,
and will keep making requests until it gets 50 responses.

That could possibly mean that, at the time it gets the last response,
there are c-1 other outstanding requests that it had made that it
will not handle/process the responses from.  

That accounts for 4 of the 5.  The other one is due to the code starting
a new request immediately after it finishes one, without checking to 
make sure that it hasn't already hit the request limit.  This one is not
counted either in the stats.