I am a very frequent user of sshfs for mounting various disks over the network. I do however have a very small machine (with an atom processor) from which I need to mount a directory using sshfs.

Is it possible to disable all compression, and perhaps even also encryption when mounting using sshfs, as to limit the cpu usage on the machine from which the directory is mounted?

  • 1
    You are dropping encryption and compression... let me think. Why don't you use FTP or SMB?
    – lajuette
    Commented Oct 9, 2010 at 7:19
  • 1
    No encryption sounds like no SSH really. Have you considered using another protocol altogether?
    – WhyNotHugo
    Commented Jul 7, 2013 at 21:18
  • 2
    @lajuette: As Dan D. states below, ssh authentication will still be encrypted, so no passwords or keys in plaintext. Also, do you know any protocol that is as readily available as ssh where I can mount remote folders as easily as I can with sshfs? Commented Mar 24, 2014 at 7:48
  • @lajuette I want the same sort of thing and my reason is that I need something my quarantined Win98 and WinXP retro-gaming machines can use to pull files off my Linux desktop PC and, of the available options, SSH via WinSCP Just Works™ through my whitelist quarantine firewall while FTP and SMB won't work, no matter how hard I try to open the right ports. (And WebDAV can apparently only be served by Apache, which is too complicated to chroot.)
    – ssokolow
    Commented Nov 3, 2015 at 0:20
  • Oh, plus, AES gives me 27Mbit throughput on the Athlon64 3200+, maxing out the CPU, while RC4 doubles that, so no encryption should get even closer to maxing out the 100Mbit NIC on the WinXP side. (Given that the rotating rust drives currently installed on both ends of the copy operations in question max out at around 200Mbit when SMB is used with contiguous files to remove the need for seeking.)
    – ssokolow
    Commented Nov 3, 2015 at 1:28

6 Answers 6


Although the high performance ssh adds a none cipher, the arcfour cipher is nearly as fast and is included standard.

Use: -o Ciphers=arcfour

I've been using this over the local network and I get about 85% of 100Mbps Ethernet or about 10.625MB/s

(In response vava's answer, sshfs would still be what it is even when ssh's encryption is off as the authentication protocol would still be active without which you might as well be using telnet.)

Note for @osgx I recently found OpenSSL: Cipher Selection which includes the following graph:

enter image description here

The following is the results section from that page. The graph and the results are questionable as they don't state how the benchmark was done and on what hardware but I think that they aren't that far off.

100,000 Kbyte/s is my threshold for acceptable performance. This represents 1 CPU core (of 8 in my case) running at 100% utilization to transfer 780Mbit/s of data (which is a reasonable saturation point for a gigabit Ethernet link).

RC4 is the fastest cipher, if you are using a processor which does not support AESNI.

AES-128 is the next fastest cipher, and much faster than RC4 if you have AESNI support. It’s about 54% slower if you don’t. AES-256 is slower still, and unless explicitly configured otherwise, any browser that supports AES-128 will also support AES-256.

What has been quoted above clearly shows that arcfour (and also AES with AESNI) can saturate a Gigabit link on a modern machine.

If you don't need encryption, the none cipher from hpn-ssh is even faster but you would only need it if you need to saturate a link with several times the bandwidth of a Gigabit link or if you need reduced CPU usage.

  • Thanks for very informative answer and this really speed up the sshfs :) Commented Jun 10, 2012 at 13:57
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    Isn't it '-o cipher=arcfour' ?
    – asalamon74
    Commented Oct 3, 2012 at 14:08
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    Will arcfour achieve 1Gbit speeds?
    – osgx
    Commented Mar 15, 2014 at 2:45
  • 1
    @osgx Yes, I would think so. See updated answer.
    – Dan D.
    Commented Mar 15, 2014 at 3:19
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    arcfour cipher deprecated and missing on most modern OpenSSH installations, You can use [email protected] instead. Commented Oct 10, 2018 at 13:56

For sftp with no encryption, use sshfs + socat

On the server side run

socat TCP4-LISTEN:7777 EXEC:/usr/lib/sftp-server

And on the client side

sshfs -o directport=7777 remote:/dir /local/dir

Source: http://pl.atyp.us/wordpress/index.php/2009/09/file-transfer-fun/

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    While this may theoretically solve the problem, it would be preferred to summarize the link contents, and provide the link as reference Commented Nov 30, 2012 at 6:15
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    By default, socat TCP-LISTEN listens on all interfaces. To limit to one specific network interface (e.g., localhost), use the ,bind= option. To allow multiple connections to the server, add the ,fork option. Making a read-only server? Add -R to the EXEC command. In the end, it will look like this: socat TCP-LISTEN:7777,fork,bind= EXEC:'/usr/lib/sftp-server -R' (on Arch Linux, I had to use /usr/lib/ssh/sftp-server instead).
    – Lekensteyn
    Commented Mar 22, 2014 at 15:51
  • For a bit more security, your can also restrict the IP range with e.g. ,range=, to only allow one particular machine to connect. Commented Jun 11, 2018 at 13:11
  • got failed to resolve [email protected]:7777: Temporary failure in name resolution .. see this answer
    – Bash Stack
    Commented Mar 10, 2021 at 14:37

There is no way to disable encryption - this is ssh after all. And it looks like compression is disabled by default as you have to request it with the -C switch.

But you may want to check your ~/.ssh/config file for settings regarding compression. If you add the following lines at the top of that file, compression should be disabled:

Host *
    Compression no

You can mount with -o compression=no to turn the compression off. It is not possible to turn encryption off, wouldn't be sshfs after that :) If it is slow I suggest to use other way to mount a directory, like through samba, nfs or ftp.

  • NFS would be a good choice
    – Jeremy L
    Commented Aug 31, 2009 at 13:00
  • The default seems to be "compression=no" anyway.
    – WhyNotHugo
    Commented Jul 7, 2013 at 21:18

I think compression is something that is really only quicker if the time to compress is compensated for by the time to transfer data. So compression on a slow connection is increasing speed up to maybe 6 times faster than without. Compression on a fast connection is not useful at all, as it drops speed due to compression delay on your or the host system. Some hosts don't accept compression at all, as they don't want to spend processor power on users.

I think this switch -o Ciphers=arcfour will increase the speed of encryption to nearly no encryption, and -o cache=yes -o kernel_cache -o large_reads -o compression=no may increase your speed a lot as it optimises sshfs a bit. Compression on low speed connections will speed up your transfer a lot if compression is possible; mostly it is. For example I do use it with a 2 Mbit/s down and 0,3 Mbit/s up connection, and it speeds up the transfer by about 3-5 minutes instead of 25-30 minutes for about 30 MByte.

  • In a way you are not giving better information than the accepted answer
    – yass
    Commented May 7, 2017 at 16:59
  • The accepted answer doesn't even mention compression. This answer may be slightly off-topic, but still has good advise.
    – Mantriur
    Commented Mar 23, 2019 at 14:19
  • gives fuse: unknown option large_reads on debian buster `
    – Bash Stack
    Commented Sep 27, 2020 at 16:37
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    it's large_read not large-reads Commented Dec 14, 2020 at 19:00

since the answer from @endru fails on recent systems with

failed to resolve [email protected]:7777: Temporary failure in name resolution

and the example only allows one connection:

  • Server socat TCP4-LISTEN:7777,fork,reuseaddr EXEC:/usr/lib/sftp-server

  • Client mkfifo /tmp/sshreturn;cat /tmp/sshreturn |sshfs -o slave,reconnect,cache=yes,kernel_cache,compression=no,allow_other,ServerAliveInterval=45,ServerAliveCountMax=2,reconnect,noatime [email protected]:/my/folder /tmp/folder | socat STDIO tcp: > /tmp/sshreturn

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