transferring large files on usb 3.1 goes from super fast to super slow

chripy811 · 04-01-2019, 07:29 PM

i have a Samsung usb drive formatted to ex4

when i transfer large files, it's very slow,

in this test, i transferd a file of 6.5GB from an ssd to a usb 3.0 flash drive using a usb 3.1 port in the back of my computer,

its starts off super fast but then gets really slow!

i thought usb 3.1 was supposed to be fast

whats going on?

heres a video of the process

https://streamable.com/ebtrz
took about 5 to 6 minutes

scasey · 04-01-2019, 07:54 PM

What distro are you on?
What is the file system on the ssd drive?
How big is the usb drive?
How much free space on the usb drive before the copy? How much free after the copy?

chripy811 · 04-01-2019, 07:58 PM

linux mint 18.1
ext4 ssd
8GB flash drive
the usb was empty before copying
there was 753MB after copying

syg00 · 04-01-2019, 09:29 PM

Don't use a GUI filemanager - try it from a terminal. There are issues with USB buffers and the memory manager sysctls, but try it as-is from a terminal before getting into fiddling the knobs.

ondoho · 04-02-2019, 01:57 AM

the file managers progress bar is probably lying.
i also find that using the cli for large files is decidedly faster than a gui fm.

JJJCR · 04-02-2019, 03:54 AM

Quote:

Originally Posted by syg00

Don't use a GUI filemanager - try it from a terminal. There are issues with USB buffers and the memory manager sysctls, but try it as-is from a terminal before getting into fiddling the knobs.

Agree with this, try rsync or just cp.

jefro · 04-02-2019, 03:39 PM

I've seen some usb flash drives that seem to have some controller issue when running ext4. Bet it you swap drives to different brand or change filesystem the problem with go away.

JJJCR · 04-02-2019, 08:48 PM

Quote:

Originally Posted by jefro

I've seen some usb flash drives that seem to have some controller issue when running ext4. Bet it you swap drives to different brand or change filesystem the problem with go away.

That's not good, not Linux friendly.

jefro · 04-03-2019, 05:25 PM

I fought a usb brand like what the OP is having for a few days. Upon testing it under ntfs I was kind of shocked to find that ext4 filesystem was causing the issue I had. Went back and forth on different filesystems and yet the result was that brand and model and ext4 just would not deliver the promise of speed. What the OP has I can't say. Testing would help. Some test, any test would help to prove or disprove any assumptions.