rsync - Oct 2004 - rsync through high latency connection

Hi,

I have a high latency, but relatively high bandwidth (1.5 Mbps) connection that
I'm trying to rsync through.  I noticed in the feature list that rsync
pipelines file transfers to minimize latency - does this only affect transfer
of large numbers of files?

Are there configuration steps that I can use to improve throughput?  For
example, is it possible to set the TCP window size to a larger number in order
to have more packets out there on the net at any one time?  If so, how?

Thanks!
Rudy


		
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On Fri, Oct 29, 2004 at 07:03:43PM -0700, Rudy Moore
wrote:
> I noticed in the feature list that rsync pipelines file transfers to
> minimize latency - does this only affect transfer of large numbers of
> files?
It should be true of any transfer, but I'd estimate that the round-trip
time gets factored in twice per transfer, so it would get amortized the
more files you include in the transfer.
> Are there configuration steps that I can use to improve throughput?
If rsync is maxing out its throughput before reaching the limits of the
network connection, it is likely that either the limits of the CPU or
the disks are being reached.  If you are using ssh for the transfer, you
can speed things up by using a faster encryption algorithm (such as
BlowFish) or by switching to rsh, or by using an rsync daemon setup
(which has no encryption).  You might also try specifying --whole-file,
which will blast each file's data in total rather than trying to compute
the remote differences and sending only the changed information.

..wayne..