sshd memory keeps increasing when client runs pscp

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[I posted this question to comp.unix.solaris with no answer yet.
Reposted here]

I run pscp (part of putty package) version 0.53b from Windows XP to
copy close to 700MB files from Solaris 10 x86 with one single command.
`df -k /tmp` on server shows that available memory gradually goes down
from the initial 688704 k to 0 and the server hangs (there're no files
under /tmp). At this moment, pscp throws error "Fatal: Incorrect MAC
received on packet". On the server, prstat shows that the number under
sshd/1 SIZE keeps going up. The number I last see before server hang is

665M (RSS is 6368K). Why does sshd use this much virtual memory, as if
it wanted to cache all the files I transfer, and how do I prevent it?
Thanks for help.

Solaris version: 5.10 s10_63 i86pc i386 i86pc
SSH version: SSH-2.0-Sun_SSH_1.1 (from telnet localhost 22;
/etc/ssh/sshd_config has "Protocol 2"; `/usr/lib/ssh/sshd -ddd` shows
"sshd version Sun_SSH_1.1")

Yong Huang

Re: sshd memory keeps increasing when client runs pscp writes:
Quoted text here. Click to load it

I don't recommend doing that. 0.53b is a rather old version with a
number of known serious security holes.
I'd recommend running 0.57 at a minimum. (The latest version is 0.58,
but you may need to apply a tweak to get it to run on XP; see the PuTTY
website's front page for details.)

(This has no bearing on your server problem, of course.)

Re: sshd memory keeps increasing when client runs pscp

[about Sun_SSH_1.1]
Quoted text here. Click to load it

Sounds like a memory leak in sshd.  Neither sshd nor scp should attempt
to cache anything during copying.

You can check if Sun has a patch for this, work around it by increasing
the limits enough to allow it to complete (assuming you have enough
swap spare) or try alternative SSH software.

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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