Comment 38 for bug 500069

Revision history for this message
Adam Kulagowski (fidor-fidor) wrote : Re: since Ubuntu karmic Filetransfer to some USB Drives got realy slow

I have Sandisk Backup U3. (32G). I've tested it on 4 different computers. I had always writing speed around 3MB/s, which is slow, because this pendrive is capable of doing 16-17MB/s writing speed. The only way I'm able to put files faster is to use dd with bs=64 AND oflag=direct. Using these options I have full writing speed.

dd if=ubuntu-10.04-server-amd64.iso of=/media/FE35-228F/file.bin bs=64k oflag=direct
10840+1 records in
10840+1 records out
710412288 bytes (710 MB) copied, 43,8788 s, 16,2 MB/s

What is also important I can break the copying proccess any time. Without oflag=direct dd ignores Ctrl-C or even kill -9.

This was tested on 10.04 and with similar result on "Recovery is Possible" distro (kernel 2.6.34-git16)

uname -a
Linux fidor 2.6.32-24-generic #38-Ubuntu SMP Mon Jul 5 09:20:59 UTC 2010 x86_64 GNU/Linux

Maybe it will help.