Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm building a RAID 6, 8 × 3 TB HDD, ext4 file system, mostly large files – 10GB or more (80%), 10-20MB (10%), 10% smaller files. The RAID contrloller is an Adaptec 6805.

How can I find out what block size I should use on my RAID controller to benefit the most?

share|improve this question
If the files are going to be large, then I'd look at the largest block size supported by the file system. – user3463 Aug 25 '12 at 21:27

Benchmarking is usually the best way to determine the best performance for a given setup. You can start testing with 64k blocks, but I suspect you will get better performance at 256k or even 512k blocks. Build the filesystem with 4k (default on linux) blocks, but make sure those 10% of smaller files do not take up all available inodes.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.