!!! Faster SSH Cipher The easiest optimization is to use blowfish. !! Ubuntu Edit {{/etc/ssh/ssh_config}}. Change {{{ # Cipher 3des # Ciphers aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc }}} to {{{ Compression yes Cipher blowfish Ciphers blowfish-cbc,aes128-cbc,3des-cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc }}} Verify by adding -v to the SSH command. !!! Multi-Core SSH Much much better with [HPN-SSH | http://www.psc.edu/networking/projects/hpn-ssh/]. See [here | http://wiki.ramp.org.au/pages/viewpage.action?pageId=3768464] for some directions on installation. I haven't yet made my own. (dead link) See [https://launchpad.net/~w-rouesnel/+archive/openssh-hpn] also. For long distance transfers, see [http://sourceforge.net/projects/hscp/]. Even if you don't use NoneEnabled/NoneSwitch, you can double the speed of the transfer because ssh won't be bottle necked by a single core. Using NoneEnabled/NoneSwitch, you can about the same speed, but with less CPU consumption. {{{ $ time rsync -e \ "ssh -v -o NoneEnabled=yes -o NoneSwitch=yes" \ --progress --inplace --recursive \ hostname:/home/username/somedir local_dir }}} Updated [link|http://blog.snapdragon.cc/2014/04/19/high-performance-ssh-install-hpn-ssh-on-osx-with-keychain-integration/] ---- [Linux.Shell | CategoryComputing.Linux.Shell] : [Networking | CategoryComputing.Networking] : [Mac.Shell | CategoryComputing.Mac.Shell] : [Performance | CategoryComputing.Performance] : [Networking.SSH | CategoryComputing.Networking.SSH]