[Click] click performance test

[Jiangbo Li]

hi, Robert Morris,

To compare with the performance of our own click elements. I am gonna
to do performance test of Click in P4 machine.

I need to add codes for each of the click elements ( at least a few of
them).
May I ask you to send me the source code which you used to do the 
performance test. It would save me a lot of time.

Thank you very much.

Jiangbo Li


> -----Original Message-----
> From: Robert Morris [mailto:rtm at amsterdam.lcs.mit.edu] 
> Sent: Monday, September 22, 2003 2:40 PM
> To: Eddie Kohler
> Cc: jblicn at yahoo.com.cn; click at amsterdam.lcs.mit.edu
> Subject: Re: [Click] click performance test 
> 
> 
> 85 cycles sounds similar to the value we measured for the cost of
> rdtsc a few years ago. rdtsc waits for the CPU pipelines to flush, so
> it's expensive.
> 
> > To: jblicn at yahoo.com.cn
> > Subject: Re: [Click] click performance test 
> > Date: Mon, 22 Sep 2003 11:35:47 -0700
> > From: Eddie Kohler <kohler at icir.org>
> > cc: click at amsterdam.lcs.mit.edu
> > 
> > Hi Jiangbo,
> > 
> > > I am doing performance test on click elements. I use RDTSC 
> > > to read the performance counter.  In your thesis, you got the 
> > > very accurate results like checkipheader takes 457ns/packet.
> > > How can you get the result so accurate? 
> > 
> > As I remember, we report the mean of several trials. We 
> didn't report
> > standard deviation numbers, so I couldn't tell you the 
> error range. As the
> > thesis says,
> > 
> > Each element's cost is the difference between the Pentium 
> III cycle counter
> > value before and after executing the element, decreased by the time
> > required to read the cycle counter; it includes the virtual function
> > call(s) that move a packet from one element to the next.
> > 
> > > Another problem is when I do two continuous RDTSC, It took 85
> > > cycles. Seems to much. Is there anything I missed?
> > 
> > Probably not; rdtsc is quite expensive; but I'm not positive about
> > particular numbers.
> > 
> > Eddie