Slow Filetransfer under Linux

After all Bill Gates has also an issue to prey on: Linux seems to be quite unefficient in transfering files from one partition (or harddisk or USB-disk) to another.

I asked for an explanation on the Linux Mint Forum.

‘optimize me’ came up with an interessting answer, which I just quote:

There is some long standing problems with how file transfers work. I never had a problem with it until kernel 2.6.24-19 came out for Ubuntu Hardy Heron back in June of 2008. At first, all I noticed is that file transfers to USB devices (flash drives, external HDDs) started moving slower than molasses in winter. CPU usage stayed below 15% or so, but transfers never went faster than 5MB/s and the speed always degraded to tens of K/s.

Research I did shows that this has been a problem on various distros going as far back as 2005. Over time, I’ve discovered that this bug is not limited to just moving files to USB devices, but also affects moving files between partitions on the same hard disk, and also affects network file transfers (both SMB & NFS).

If you look at your system monitor in the panel (I assume that’s what you’re using), and change the color scheme of your CPU monitor(s) to highly contrasting colors (Red, Blue, Yellow & Green, for example), you’ll see that what’s termed as “I/O Wait Time” is what’s eating up all your power. I’ve been up and down a million forums, been in contact with kernel and module developers, and spent countless hours researching the problem.

I’ve got zilch.

All I can tell you is that the problem doesn’t effect everyone – only, it seems, a small minority – so it’s not at all a priority for the developers to fix. You can do a google search for “slow+usb+linux” or “slow+usb+ubuntu” and you’ll probably find all my forums posts and all the same info I found. I’m not a programmer, I’m not a developer, and I don’t know jack about where to even begin tackling this problem. That’s where that stands.

I inserted some linebreaks for readability. Thanks a lot ‘optimize me’.


.dmrc Beeing Ignored

After installing the Fluxbox desktop in addition to the default Xfce4 in Xubuntu a persistent error message started to show up:

User's $home/.dmrc file is being ignored. This prevents the default session and language from being saved. File should be owned by user and have 644 permission. User's $home directory must be owned by user and not writable by other user's.

It seems to be a bug in Ubuntu. It turned out that the same error message appeared on a Ubuntu Jaunty (Gnome) fresh install and on my Linux Mint 7 (based on Ubuntu Jaunty) fresh install. From time to time it shows up and I have not figured out how to (re-)produce it.

chmod 644 .dmrc
chmod o-w /home/USER

does the job, where USER has to be replaced by you username.