Tuesday, 23 December 2008

Ext3 vs NTFS

During my bi-anual hard disk cleanup, I had a choice to make. Every two years (or so), I upgrade my backup disks to larger capacity. This year, I got several 1 TB hard disks from Samsung (they are fast, quite, reliable, and keep cool).

As I have been using Ubuntu for more than a year without any major problems, I thought of using a native linux file system on my backup disks. What would I want to use NTFS for anyway?

I formatted the first disk to ext3. Next I copied a full 250 GB hard disk to the drive. The whole drive took 3 1/2 hours to copy. The disk was evenly populated with small, medium and large size files. When I was finished, I was quite surprised that a 250 GB NTFS disk (233 GB netto data) would require something like 360 GB disk capacity on an ext3 formatted drive (including an offset ot 14 GB disk overhead).

There are ways to format hard disks specifically to ones needs, reducing overhead and tayloring meta information to a minimum. But using the tools offered by the GUI, you have to make do with the defaults.

In a second round, I formatted the same disk to NTFS. Used space was 233 GB (which would not surprise anyone).

So, if disk space on ext3 is used more freely, is the file system faster?

I timed the copying, using an idle notebook. Here are the results:

FSMB/secMB on Disk
NTFS windows formated13.1233,5
NTFS ntfs-3g formated17.1233.5
Besides the fact that formating a 1 TB disk for ext3 takes some time as opposed to NTFS which takes just seconds, the NTFS file format seems to provide higher transfer rates on Ubuntu while maintaining a smaller footprint on the disk.

Further tests showed a degrading performance when the disk (or directory) gets filled up. After having filled 3/4 of the disk, transfer rates lay at around 4.5 MB/sec.


I have not looked into this in a statistically valid way. File system layout, file size and other aspects have not been covered. From the point of disk space usage, it seems that NTFS is more efficient.

If you want to share your own observations, I look forward to reading from you.

Sunday, 21 December 2008

Upgrading 8.04 Server -> 8.10

Ubuntu 8.04 is a Long Term Support (LTS) release. This implies that automatic upgrades to later releases are supressed in favour of having a stable system.

If one wants to upgrade from 8.04 to 8.10 (server edition) one has to edit the file
Search for the string:
and change it to:
(as described in the comments of the file). Now you should be able to run the upgrade utility:
sudo do-release-upgrade
This will start the upgrade process.

If you have followed previous hints on upgrade in this blog, you might have the upgrade-manager-core utility installed on your system (which includes do-release-upgrade). If not, you have to install it with sudo apt-get --install.

Upgrade takes approximately 20 mins on my server and requires a reboot to finalize the installation process.