ssh / scp slow on 10GBE

Stefan Priebe s.priebe at
Thu Jan 3 09:29:14 EST 2013

Hello list,

right now SSH Tunnel / scp is reaches just around 76Mb/s on my E5 Xeon 
using AES-NI but openssl reaches around 600-700Mb/s using 128aes-cbc cipher.

As far as i understand this is due 
to very small buffers in ssh / scp.

Is there any work on this? Like autotuning the buffer size? Are there 
plans to integrate the hpn patches?


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