I suspected that btrfs partitions are kind of sluggish compared to ext4 when performing many small operations, so I benchmarked three separate partitions on the same hard drive, one ext4, one btrfs, and I threw in NTFS for good measure. This was done on a hard drive which was formatted between tests so only one partition was on it at a time, and each partition used the entire space on the drive. I copied over many small files, and ran the command shred -fzuv * on it, which overwrites each file multiple times with junk data and then wipes the file name by repeated renaming it.

This showed that the btrfs partition is much slower than ext4 or NTFS, which is particularly noticeable on the renaming steps. I could also hear the drive clicking furiously the whole time for all tests, so I think it’s safe to say that none of them had the drive sitting around for much of the test.

Is this normal? As in is btrfs supposed to be a lot slower on random operations than simpler files ystems?

  • Ephera
    8·
    4 years ago

    I don’t understand terribly much about all of this, but BTRFS is a CoW (Copy-On-Write) filesystem, so as I understand it, write operations will always be rather slow. So, with your benchmark being basically just writes, it’s probably not representative.

    Having said that, I think, reads can also take somewhat of a performance hit on HDDs (because the data gets spread around when the CoW happens).

    Ultimately I’m assuming NTFS is slow, because Microsoft, but BTRFS might very well be slower, because it has an actual reason to be slow. Its selling point are the features, not the performance.