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Re: libcurl takes long time to connect to CoreFTP's SFTP service

From: Daniel Stenberg <daniel_at_haxx.se>
Date: Wed, 10 Feb 2010 23:41:16 +0100 (CET)

On Wed, 10 Feb 2010, Xu, Qiang (FXSGSC) wrote:

> I am using libcurl (together with libssh2) to do SFTP transfer, using SFTP
> service provided by CoreFTP. Yet, I found it costs a lot of time for each
> session.

Is that a recent libssh2 version?

> To my surprise, it takes more than 10 mins for a simple connection. I don't
> know if the message "Failed to stop libssh2 sftp subsystem" is implying
> something.

I don't think it is strictly related to the slowness. However, it would be
if you used --trace-ascii and --trace-time to get output that is annotated
with its time to better give us a clue where all that time is spent!

> In contrast, when SFTP service is provided by OpenSSH, the session is
> finished much more quickly.

OpenSSH's SFTP implementation is much faster than libssh2's, but it shouldn't
result in something other than a 2-3 times(!) faster transfer.

-- 
  / daniel.haxx.se
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Received on 2010-02-10