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Re: scp troughput



Joerg Sonnenberger <joerg%bec.de@localhost> writes:

> On Mon, Aug 19, 2019 at 11:04:28AM -0400, Greg Troxel wrote:
>> I am guessing you have GbE wired, so you have < 1ms round-trip ping
>> times; I'm seeing 0.330 ms ping times even with a  2014 box and a 2008
>> laptop.
>
> In the context of ssh, ping times are somewhat misleading. The real RTT
> for the purpose of finding the bandwidth delay product needs to include
> the crypto latency, which can be quite significant.

True.  I was just trying to establish if we were talking about a
well-functioning local wired GbE.

In my traces, I am seeing bursts that are likely to have about 16kB of
data (in 12 packets), about 700 uS apart.  Which is about 23 MB/s.

So far, it looks like the window sizes are much smaller than I'd expect
given the recvspace/sendspace settings (131072).




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