Switching from ext3 to ext4

My desktop at home was bought and installed in May 2007. Since then it has aquired more RAM and an SSD and it was upgraded several times to the newest Debian release.

However, my /home filesystem was still ext3 — just as I created it more than 9 years ago.

But today I ran my old bench program and the write performance looked like this:

writing 7GB with decreasing speed of 24 MB/s average

7 GB at an average speed of just 24 MB/s? And it gets slower and slower? On an SSD? That's ridiculous. Is my SSD on the fritz? But no, it's spending almost all time in the kernel, not waiting for I/O.

So I created a new, empty ext4 filesystem and rsynced my data over:

Much better. The write performance is now almost constant at 250 MB/s. A bit surprisingly, it is even slightly better on the filled filesystem (purple) than on the freshly created empty filesystem (blue).

I don't know whether ext4 is so much faster or whether the file system was just so badly fragmented after 9 years of constant use, but it does pay to upgrade your file systems every once in a while.

$Date: 2016-10-06 15:59:50 +0200 (Thu, 06 Oct 2016) $