I have noticed that on my office's network, multi-hop SSH connections using the "pseudo-tty" method perform better (see last note) than using the "forwarding" method. Why would this be the case?
In other words, why would:
ssh -A -X -tt server1 ssh -X -tt server2 # pseudo-tty
result in much better performance than:
ssh -o ‘ProxyCommand=ssh -A -X -W %h:%p server1’ -X server2 # forwarding
- I'm on my laptop, and server1 and server2 have the same hardware.
- On my laptop, I've got Windows 7 with Cygwin's ssh and xwin. It has a decent processor (i7 4610M or similar).
- Both server1 and server2 are RHEL 6.5.
- I haven't measured bitrate, but X11 apps are significantly faster with the pseudo-tty method (there's visible delay with forwarding).