Ask Ubuntu is a question and answer site for Ubuntu users and developers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

since quite some time i'm running ubuntu on an external hard disk, connected to the PC via USB. This works quite well. I recently got a 32GB USB stick and i installed (so no live USB) Ubuntu 11.10 on it. I found this more practical because smaller than a hard disk. BUT the OS it is running a lot slower than with the HD. I checked transfer rates and compared with the HD and it looks as if the USB is quicker than the HD. Any idea why? I partitioned the USB stick like this: first a swap area of about 2GB, then the ext4 root partion and last an NTFS partition.

share|improve this question
if your 4Gb USB was USB 2.0 then it wasnt "falling back" to USB 2.0 but using it and "falling back" only to USB 1.0. "Falling back" means running at falled back speed. – Kangarooo Dec 23 '12 at 3:23

USB Flash drives performance is inferior to traditional hard drives. It's just a different technology and not as fast. The illustrious Jeff Atwood has an article explaining this in detail on his Coding Horror site, where he goes into more detail. Lots more detail.

share|improve this answer
  1. Get the fastest drive you can afford (so-called 150x or better).
  2. Change to a non-journaled file system. Ext2 is good.
  3. Edit /etc/fstab to enable async I/O.
  4. Disable swapping - don't make a swap partition or file.
share|improve this answer
Are you sure that ext2 faster than ext4 for installed Ubuntu at slow usb? – Vitaly Zdanevich Nov 7 '15 at 18:43

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.