Subject: [libssh2] Speed and 'lockup'

[libssh2] Speed and 'lockup'

From: Cary Fitzhugh <>
Date: Mon, 21 Jan 2008 10:06:12 -0500

Hello -

We've noticed a slowdown of ~10x on downloading a file, as opposed to
uploading a file. It seems that the discrepancy is in libssh2. openssh
sftp puts and gets at about 7MB/s on our network. Libssh2 puts at
around 6MB/s and gets at around 400kb/s. Does anyone know why this
might be the case? I'm willing to look into it and do some work on the
code if someone could point me in the right direction. Looked at
ethereal captures, and seems like the packets are just 10x slower in
being transmitted. I don't see any broken packets or anything that
looks out of the ordinary. To me at least.


Also - we've seen a periodic hang when using curl & libssh2. We'll get
into a situation where we transfer at about 2kb/s - so the connection
isn't closed, but a 300 MB file won't finish transferring any time soon.
Has anyone else seen this - or does anyone have an idea as to where I
could look to debug it? I haven't verified if it is in curl or in




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Received on 2008-01-21