[OpenAFS] Re: WAN speed

Andrew Deason adeason@sinenomine.net
Thu, 22 Mar 2012 10:09:41 -0500

On Thu, 22 Mar 2012 10:18:44 -0400
chas williams - CONTRACTOR <chas@cmf.nrl.navy.mil> wrote:

> but besides this limit, there is also another determining factor in
> rx.  rx, like tcp, negotiates a window of data to send before waiting
> for an ack from the other side which lets me data get sent.  if the
> window doesnt grow large enough, then you will not be able to get the
> full bandwidth of the link.  i believe usually, you hit the window
> size limit in rx before anything else though.
> there are some problems with using larger window sizes in rx related
> to queue management efficiency as i recall.

But even without that, the window size still has a limit much smaller
than TCP.

Jukka, can you give the bandwidth and latency for the connection you're
accessing over, and the speed you're expecting from it? (Just a latency
estimate from 'ping' or whatever, from the client to a fileserver, if
the network between the two machines allows it.) You mentioned a 100m/5m
connection before, but not how big the delay is to a fileserver.

Andrew Deason