scp vs ftp performance on SGI IRIX????????

Darren Tucker dtucker at
Fri Nov 7 07:35:57 EST 2003

Jay Chen wrote:
> Running OpenSSH 3.5p1 or 3.7.1p2 on two SGI orgin 300 systems of IRIX
> 6.5.17 with
> 4 600MHz CPU and gigabits network.
> Transfer a 1GB file with ftp took 28 seconds.
> Transfer a 1GB file with scp took 148 seconds.
> Use "snoop" to capture all network packets between these two systems. Ftp
> tansmitted
> about 107840 packets, but scp transmitted about 763339 packets.

Wild guess: does changing the shell pipe size (probably "ulimit -p") make
any difference to scp?  What's it set to by default?

Also, do you have compression on or off?

Darren Tucker (dtucker at
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

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