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I am trying to transfer large files over an internal network using Secure Shell SSH Client (3.2.9). The default buffer size is 32KB, which should be plenty, but my specific case makes me wonder if I could get a faster/more reliable transfer by increasing it:

  1. The transfer is one-way. From a server running Unix, directly to a 1TB HDD attached to the desktop via eSATA. The local OS is Windows 7.
  2. I am transferring 24x 15GB text files for a DNA experiment.
  3. The current speed is averaging 12MB/s (buffer size=32KB)

Basically I've let the transfer run a couple hours and keep getting a fatal error "Out of Memory," even though I'm not even using half my 8GB RAM. Could upping the buffer size help?

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migrated from Oct 7 '12 at 22:36

This question came from our site for professional and enthusiast programmers.

You could always .. just try changing the buffer size .. no need to post a question to see if the setting change would make a noticeable difference. There are secondary questions here - e.g. "How to avoid OOM when transferring files via SSH?", which is OT - but it's all muddle together and presumes one thing has an effect on another. – pst Oct 3 '12 at 2:08

Something is probably wrong with your SSH client. Try doing the same with putty's pscp.

More reliable.. It doesn't get more reliable than TCP :) Regarding speed, SSH shouldn't be a bottleneck. 12MB/sec sounds like 100Mbps, so unless you're on a 1Gbps network all the way it sounds about right.

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