Re:Btrfs in Linux 6.2 brings performance improvements, bette...
by matheusmoreira on Tuesday December 13, 2022 @07:34AM
(#33968047)
Yeah but DM doesn't have the btrfs flexible block allocation scheme that allows me to expand capacity one drive at a time and with drives of different capacities. This is very important for a home user like me.
To expand a typical RAID setup, you have to essentially fail every single drive in the array and replace them one by one with new identical drives. Expanding an array of N drives requires N resilvers which not only takes a long time but increases the chance of actually failing those drives due to massive I/O load. It's easier to build a second array and copy the data over. This combined with the fact you have to buy all the hardware up front makes it cost prohibitive for home users. You can't buy drives one at a time and expand capacity as needed.
To expand a typical RAID setup, you have to essentially fail every single drive in the array and replace them one by one with new identical drives. Expanding an array of N drives requires N resilvers which not only takes a long time but increases the chance of actually failing those drives due to massive I/O load. It's easier to build a second array and copy the data over. This combined with the fact you have to buy all the hardware up front makes it cost prohibitive for home users. You can't buy drives one at a time and expand capacity as needed.