The Ping servlet

[Roy Wilson <de...@bellatlantic.net>]

>>>>>>>>>>>>>>>>>> Original Message <<<<<<<<<<<<<<<<<<

On 11/8/00, 10:48:07 PM, "Remy Maucherat" <re...@apache.org> wrote regarding 
Re: Thruput, response, and perf servlets:


> Thruput, response, and perf servlets>Remy, I should have said 
"throughput,
> as in number of requests
> >processed per second". My point is that if  some servlet S requires TC
> >to use more disk+cpu than the HelloWorldExample on a particular
> >machine, then TC's processing rate for S will be lower than it is for
> >the HelloWorldExample.

> It does way more than nothing, as Costin (I think) pointed out :
>         ResourceBundle rb =
>             ResourceBundle.getBundle("LocalStrings",request.getLocale());
>         response.setContentType("text/html");
> So there's disk access (which is very bad).

All software does something, yes? (even if it's only a no-op).

> For maximum number of requests / s, I need a servlet whose service 
function
> is empty.

I'm confused: I don't see how what I've said  and the above statement are 
in disagreement.

> >Yes, but the response time for processing HelloWorldExample servlets
> >should be less than the avg response time for processing a servlet S
> >which "does more" than HelloWorldExample.

> With the IO caused by the resource bundle loading, I'm not sure.

I was trying to make a general point, which is also (I think) what Craig 
was up to, not a statement about a particular servlet. Unfortunately, he 
and I both used the HelloWorldServlet to illustrate that point.

> >I think we agree, but stated things differently. Or, maybe not :).

> We do, but the HelloWorldServlet does more than :
>         PrintWriter out = response.getWriter();
>         out.println("Hello");

> >A kind of synthetic workload? There are commercial products that do
> >that sort of thing, I think.

> Great. It's not that I don't like commercial software, but I think we 
could
> use a free test suite.

> >So, I propose a workload model based on servlets we already have (or
> >could develop for). Starements about TC performance are relative to a
> >transportable set of requests and there is no need to get into wars
> >about which version of TC is better. Too simple, I know. This is a bit
> >like what you propose about a "perf" webapp maybe?

> Np. I still want the maximum performance case, though ;) Real people will
> probably not be interested by it, but developers who may want to help
> optimizing Tomcat would find them helpful.
> Could we do both so that everyone's happy ?

Yes (but since when can everyone be happy? :-))

In "Java Performance and Scalability, Vol 1", Dov Bulka takes a similar 
approach to what you've described, I think. He defines a PingServlet, 
which he describes as "the world's fastest servlet" and uses it as a 
baseline for evaluating the perf of more "real" servlets. He also 
describes it as a "performance upper bound": it provides a way to 
"evaluate the upper limit on the throughput of the web application server 
under  test." 

I can send the PingServlet code if you're interested.

Roy 

> Remy


> ---------------------------------------------------------------------
> To unsubscribe, e-mail: tomcat-dev-unsubscribe@jakarta.apache.org
> For additional commands, e-mail: tomcat-dev-help@jakarta.apache.org