Heckroth Industries

Filesystems

Comparison of ext2,3,4 and ntfs on usb flash drive

There is a topic over on the Hak5 forums asking which filesystem format is best for use on a USB flash drive. I figured that I would run some basic tests and see if my results match up with other tests on the internet.

I decided to test 3 different types of operation, reading, writing and deleting. Each test on each files system was performed 10 times with the results averaged and then plotted onto graphs.

Each test tested tested 11 different sized files (1KB, 512KB, 1MB, 2MB, 4MB, 8MB, 16MB, 32MB, 64MB, 128MB, 256MB).

The filesystems were all tested on a 4GB Dane-elec flash drive over USB2.0 on my eeePC 900 running Linux.

Reading

Before performing the reading test the disks were synced and the file cache dropped to try get an more accurate measure of the filesystem instead of the file cache.

The results from the read performance tests showed ext2 and ext4 performed the best overall, with ext2 having a slightly better performance than ext4 on the larger files.

An interesting result is the way that ext3 really seemed to struggle with reading the large files. The performance from ntfs was slower than than ext2 and ext4.

Writing

The writing performance tests showed again that ext3 seemed to struggle as the file size increased. A bigger gap is also shown between ext2 and ext4 with ext4 standing out as better with the larger file sizes.

Interestingly once the file sizes get beyond 32MB ntfs stands out as the best performer for writing.

Deleting

ext3 and ext4 perform the worst at deleting the larger files while ext2 performs the best. Again ntfs is worst than the other file systems on smaller files but performs better than ext3 and ext4 on the larger files.

Conclusion

Based upon these results I would recommend ext4 as it does a good job with reading and writing and while slower than the others at deleting larger files it is still capable of deleting and 256MB file in less that an eighth of a second.

It would be interesting to run these tests on existing file systems which have been used a lot to see if there is a difference after files have been added and removed repeatedly (which is quite common with USB flash drives).

Of course if you are going to be using the drive on a windows machine then ntfs would make much more sense.

Jason — 2011-01-12