Oooo this is exciting. One of the annoying things about "traditional" raid is that making a raid group gives you performance, but it also kneecaps your rebuild

Oooo this is exciting. One of the annoying things about "traditional" raid is that making a raid group gives you performance, but it also kneecaps your rebuild time. This is because you need to do a coordinated read from each disk in the raid stripe by stripe. a rebuild is effectively a single threaded synchronous operation We don't really need to have such rigid mapping of data to raid groups anymore. which is why most large storage systems partition your data up into small chunks (a few megs) apply some forward error correction to it, and smear it all over the place. This means that you can do multi-threaded rebuilds. This means that as your array gets bigger, not only does the rebuild time get smaller, but its much more resilient to data loss. A good example of this is GPFS's native raid: https://www.usenix.org/legacy/events/lisa11/tech/slides/deenadhayalan.pdf https://www.usenix.org/legacy/events/lisa11/tech/slides/deen... (https://www.youtube.com/watch?v=2g5rx4gP6yU https://www.youtube.com/watch?v=2g5rx4gP6yU) A word of warning though. Don't do this for small arrays (<50 disks) its not worth the hassle, yet.