You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

General Purpose RAID 0 "Chunk Size"?

fyi: using macOS 13 Ventura on a Macbook Pro M1 Max.


i have an older Western Digital My Passport Pro with a Thunderbolt 2 interface (using an Apple Thunderbolt 2 to 3 adapter/dongle). it's the one with 2 HHD's in it.


it came setup as RAID 0 but formatted in "Mac OS Extended (Journaled)". i want to reformat it to use "APFS" instead.


so using Disk Utility, i deleted the RAID and reformatted the drives. then upon using Disk Utility's RAID Assistant, i selected the RAID type to RAID 0 and selected the two newly reformatted drives. then on the next screen (Set Properties), under where you choose the Name & Format, there's a setting to select a "Chunk Size".


i've never seen this option before (granted it's been many many many years since i needed to re-RAID something), and i can't figure out which option to select...


the Chunk size options are: 16K, 32K, 64K, 128K, or 256K.


everything i've found to read on the subject says that's determined by how big the files you're working with are. to choose a small K when working with large videos & graphics files; and to choose a large K when working with smaller text based files.


but what if you have a mix for ALL kinds of files & sizes?


what would be the optimal Chunk size for a general purpose drive?


yes, i could just choose the middle one (64K) but i don't know if that's optimally average or if leaning to the left or right of middle would be better for such a mix of file types & sizes.


i did contact WD support and instead of just telling me what Chunk Size the drives came from the factory set at, their 'only' solution is for me to download/install their disk utility app. i had problems with that app working well two computers ago, so chose to not install it on my previous & current systems. i would rather a solution to be knowledge rather than 'another' app to clutter my mac innards just for this purpose. thanks.


MacBook Pro 16″, macOS 13.3

Posted on May 21, 2023 10:26 AM

Reply
Question marked as Top-ranking reply

Posted on May 22, 2023 1:25 PM

FYI: i asked this same thing & got a satisfactory answer over @ https://apple.stackexchange.com/questions/460163/how-to-discover-choose-raid-chunk-size

Similar questions

1 reply

General Purpose RAID 0 "Chunk Size"?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.