[TAG] MTR over a CDMA link (cell phone)

[Ben Okopnik]

On Mon, Apr 05, 2004 at 10:58:47PM -0400, Jay R. Ashworth wrote:
> On Mon, Apr 05, 2004 at 10:56:54PM -0400, Ben Okopnik wrote:
> > On Mon, Apr 05, 2004 at 10:01:36PM -0400, Jay R. Ashworth wrote:
> > > 
> > > No, but windowing will keep latency from affecting bandwidth.  The
> > > thing that impacts bandwidth, on a TCP stream, is the combined
> > > latencies of packet transmission, packet turnaround at the receiving
> > > end, ack transmission, and ack processing at the local end.
> > 
> > [Nod] Right, my mistake in interpreting "latency" this time (duh!
> > You'dathunk, by now...)
> 
> And now you understand why *I* had trouble before.
 
Oh, I knew it was a context-related problem right from the start. My
problem was that after grinding on "system latency" for so long I was
still stuck on it when we started talking packet latency.

> > > The more packets you're permitted to have in the window, the more
> > > bandwidth you can get out of a given amount of total latency... at the
> > > price of a bigger stack of dominos hitting the floor if you don't have
> > > a perfect link.
> > 
> > Sure; now I gotcha. Packet latency affects small chunks of data much
> > more than it does large ones, of course.
> 
> Well, by percentage, yes, but it's the *empty* hose that kills you on
> long-latency pipes.  Windowing allows you to fill up those holes.

Sure.

> > > Damn.  I'd thought you were.  I'll look at it someday, but it's damned
> > > inconvenient not to be able to mail the output to someone... and since
> > > it clears the screen on exit, you can't even copy and paste
> > > conveniently.
> > 
> > So, why can't you just copy and paste it while it's running? I just
> > tried it, and there doesn't seem to be any evil magic about that would
> > prevent it.
> 
> I don't have good enough aim to do a complete select in the
> less-than-one-second I have available between updates... which seem to
> interrupt Konsole's select process.

Try running it in an xterm - the current screen state "freezes" as soon
as you start the selection. The above behavior sounds broken to me, at
least in terms of The Right Thing for most scenarios. 


* Ben Okopnik * okopnik.freeshell.org * Technical Editor, Linux Gazette *
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