[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Reverse port forward channel performance


Hi Aris,

I'm not sure if it's significant but the logs from the port forwarding implementation show that the function 'channel_rcv_change_window' makes changes to the window size but in the reverse port fowarding implementation, changes to the window size are executed via the 'grow_window'
function.

 - Gearoid

On 27/01/12 20:42, Aris Adamantiadis wrote:
Hi Gearoid,

It's possible that channel windows are not initialized the same way in forward and reverse forwarding. This could result in bad performances if the window is too small.

I'll check if I can find anything.

Aris

Le 27/01/12 18:16, Gearoid Murphy a écrit :
Hi,

We've been observing poor throughput (230KB/s) on libssh channels
generated from reverse port forwarding (ssh_forward_accept) via an
OpenSSH server.

Conversely, when using a channel generated through a normal port
forwarding call (ssh_channel_open_forward), we observe far greater
throughput (8MB/s).

Has anyone observed or experienced similar issues?, is there some
configuration aspect of the channel setup which needs to be modified?

libssh 0.5.2-1
Linux 3.0.0-15-generic x86_64 x86_64 x86_64 GNU/Linux
openssh-server 1:5.8p1

Thanks
- Gearoid





Follow-Ups:
Re: Reverse port forward channel performanceGearoid Murphy <gearoid.murphy@xxxxxx>
References:
Reverse port forward channel performanceGearoid Murphy <gearoid.murphy@xxxxxx>
Re: Reverse port forward channel performanceAris Adamantiadis <aris@xxxxxxxxxxxx>
Archive administrator: postmaster@lists.cynapses.org