RAID block size

I am reformatting my LaCie 1TB SSD Thunderbolt2 to Striped RAID. The question is what raid block size should I use. The options I have in disk utility is 32 up to 256. Any ideas ? I only use this drive for my FCPX libraries including all my media.

Whatever the default is, use it.

I made some research on this matter and found out, that the default 32 is good for light common computer work but on many sites I visited the recomendation for video editing with large files are 128 or 256. I set it to 256. I can not tell if this makes any difference yet. I had some issues with Disk Warrior, constantly telling me to rebuild the directory, but after the change to 256 I have not had any issues with the directory.

Makki wrote: I am reformatting my LaCie 1TB SSD Thunderbolt2 to Striped RAID. The question is what raid block size should I use. The options I have in disk utility is 32 up to 256. Any ideas ? I only use this drive for my FCPX libraries including all my media.

In general the optimal configuration would be stripe size equal to the approx. average I/O size for the main workload on that drive. You can very roughly approximate the I/O size of a given workload by using Activity Monitor, and dividing bytes per sec by IO per sec. Apps in this category often use fairly large average I/O sizes. Here is some testing I did on a Pegasus R4 in RAID5. This focused mostly on the impact of stripe size to RAID initialization, but I also did runtime performance tests.

forums.macrumors.com/showpost.php?p=18576138&postcount=1

SSD has different behavioral characteristics than spinning disks; random I/O is especially faster. This can change the normal advice for stripe size. In general I wouldn't worry about it. What Ben said is good advice; unless you have clear evidence to the contrary, picking the default is a good idea.

I think your LaCie 1TB SSD is 2x 512GB SSDs, so you're talking about a two-drive RAID0 configuration. In theory that's faster but SSD is already so fast I'm not sure how much practical difference that makes, regardless of stripe size. But if in doubt, just take the defaults.

Thank you so much for this good information. I will now review my decicion.

Best
Makki

Just some trivial background;

There was as time way back when we rode to work on dinosaurs, when you did have to optimize a drive (defrag) and set block sizes properly. Way back when a 20 MB drive was the size of today's VCR, and was as loud as a 747 at takeoff. Anyone remember "Rodime" with the Mac Plus? Yeah, I'm aging myself here. Today, most of that stuff is trivial and isn't that important, because drives are MUCH faster (not just rpm, but read/write speeds) and much more stable.

Good comment, Ben, when it comes to speed, the main problem is my brain but I think it is not ugradeable