[CLUE-Tech] Network DD

[Timothy C. Klein]

* Jed S. Baer (thag at frii.com) wrote:
> On Tue, 30 Apr 2002 21:31:58 -0600
> "Timothy C. Klein" <teece at silverklein.net> wrote:
> 
> > Hey all,
> > 
> > I just made changes to the way I load my network module, and it
> > supposedly will have improved my throughput.  A test with SSH seems to
> > have confirmed this, but I want some kind of bandwidth test without all
> > the overhead.  I want to see how close I am to saturating the 100 Mb/S
> > that I supposedly have.  What would be the network equivalent of dd?
> > How do I send raw 0s across the wire?
> 
> Have you tried netcat?
> 
Ah, thanks.  I *knew* I had heard of something that would do this once.
And as I supsected, my throughput doesn't seem all that great.

Anybody want to check my numbers?  100 Mb/s = 12.5 MB/s (in decimal
megabytes, rather than 1024.  Than just complicates things).

When I transfer the kernel with the ncp script provided by netcat, it
takes 6.295 seconds of real time (as reported by time), and the file is:
23,841,012 bytes / 6.295 s = 3,787,293 bytes / second.  This seems to be
about one quarter of max.  On both ends I have a 3com 3c59x card.  Seems
low to me.  Also, ssh didn't have nearly the overhead I expected.  It
does the same file in 6.444 seconds.  

Any ideas?
Tim
--
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== Timothy Klein || teece at silverklein.net   ==
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== "Hello, World" 17 Errors, 31 Warnings... ==
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