Question Ubuntu SFTP speed slow

nicolasbeiglboeck

Prominent
Mar 14, 2018
4
0
510
I got a problem with my ubuntu vps Server..
I dont know since when this happens, but I noticed it today while uploading a file on my Server with filezilla.

Problem: When uploading a file to my server, the max speed throttles on about 200kb.. But on the server of my friend (same hoster and even has a slower internet conection) I get up to 1,5 to 2 MBs per second..
I already googled and found this command: sudo sysctl -w net.ipv4.tcp_sack=0 and sudo sysctl -p
After executing those, my speed did improve, but only up to like 500KB.. The Internet connection of my Server defenetly cant be the problem (http://prntscr.com/ngh4h8)
Every help appreaciated!
 
Did you test both servers from the same pc/connection?
Is your ubuntu server on arm or anything? AES can run slow on some stuff. 2MB AES doesn't take too much though.

I'd recommend checking the encryption type setup. AES 128 CBC / SHA1 is used a lot; it's not considered 100% secure anymore. 256b AES GCN with no hardware crypto could result in speeds that slow on low end hardware. that algo drops about 90% with no hardware accel. even with AES-NI it caps out around 250Mbs on high end hardware. GCN should only be used if the server can negotiate it's encryption type or you're positive all the clients have hw AES.
 

nicolasbeiglboeck

Prominent
Mar 14, 2018
4
0
510
Did you test both servers from the same pc/connection?
Is your ubuntu server on arm or anything? AES can run slow on some stuff. 2MB AES doesn't take too much though.

I'd recommend checking the encryption type setup. AES 128 CBC / SHA1 is used a lot; it's not considered 100% secure anymore. 256b AES GCN with no hardware crypto could result in speeds that slow on low end hardware. that algo drops about 90% with no hardware accel. even with AES-NI it caps out around 250Mbs on high end hardware. GCN should only be used if the server can negotiate it's encryption type or you're positive all the clients have hw AES.
My ubuntu server is a VPS, i rented it on a hosting platform.
Just to let you know it has 10 cores (good server cpu) and 60GB RAM and 1 GB band.

Well.. I'm actually not that experienced with ubuntu yet.. Where can I check the encryption type?

But already thanks!

Edit: And yes I tested it from the same PC and Network.
 
Maybe try normal FTP to just test. You do not want to leave a server up when you are not testing. This will show you if it is the encryption.

You also need to transfer 1 large file rather than lots of little ones there is a lot of overhead creating the file names and directories.
 
My ubuntu server is a VPS, i rented it on a hosting platform.
Just to let you know it has 10 cores (good server cpu) and 60GB RAM and 1 GB band.

Well.. I'm actually not that experienced with ubuntu yet.. Where can I check the encryption type?

But already thanks!

Edit: And yes I tested it from the same PC and Network.

Even if you used the worst it would be faster than 200k on x86 cpu.

You can check by typing sshd -T
under ciphers it's ordered 1st priority to last. You would have to check the client and server and the first order match on each would be the one it uses. Since your internet is so fast I'd suggest the chacha20/poly1305. you can play with it on the client later once you figure out the current bottleneck.
 
Last edited:

nicolasbeiglboeck

Prominent
Mar 14, 2018
4
0
510
Even if you used the worst it would be faster than 200k on x86 cpu.

You can check by typing sshd -T
under ciphers it's ordered 1st priority to last. You would have to check the client and server and the first order match on each would be the one it uses. Since your internet is so fast I'd suggest the chacha20/poly1305. you can play with it on the client later once you figure out the current bottleneck.
hm well.. seems to be my client.. I just tested to upload the same file from the same network but with my phone.. And i got my 2 Mb/s.. Any Idea what I can do? I did already test it with WinSCP and speed is also slow there..