Subject: RE: SFTP download speeds

RE: SFTP download speeds

From: Mononen Jussi <>
Date: Tue, 14 Dec 2010 20:58:14 +0200

> > When we use this approach we have a significant over-read
> for small
> > files. If we for example were to write an application that
> moves over
> > a directory with 100 files, each being 20 bytes, we would perform
> > terribly slow and waste a lot of bandwidth.
> One approach could be to use a slow-start that only queues a
> few over-reads at the start, then increases the window
> exponentially to a maximum of 4 MB as data is read. This
> shouldn't penalize the small file case much while (hopefully)
> allowing large file transfers to happen reasonably quickly.

AFAIK this is what OpenSSH does, it starts with few packets and then starts to fill the bandwidth.

Amazing improvements on perf!


You have to step outside the box to see it.
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Thank you.
Received on 2010-12-14