Storage Spaces Parity Raid intilization period??

[Computurd]

hey guys, with RAID controllers when you build a RAID 10 or a RAID 5, for instance, you have to wait for the volume to build (initialize) for a period of time before there is full performance.

However, when setting up storage spaces with Parity in Server 2012 it doesn't show ANY initialization counter. It still has to initialize one would imagine, but where is the counter?

Even when creating RAID arrays using the disk mgmt pane the old school way there is a RAID initialization period.

Any ideas?

 

[drescherjm]

Some raid (including zfs) skips the full array initialization and instead initializes each stripe as it is written.

 

[omniscence]

Any RAID function that is integrated into the filesystem does not have to do initialization as it is fully aware of which stripes do contain valid information. They just fill the stripe with consistent data as soon as it is needed. RAID functions below the filesystem have to intialize because they do not know which stripes are actually used by the filesystem above and thus have to make sure all of them are consistent from the beginning.

Of course it would is possible to skip the initialization (I do this when benchmarking RAID implementations for example), but then the content of all unwritten sectors is undefined and may even change in case of parity recovery. And that way the initialization is just moved to the first parity check, which will just throw up a lot of parity errors with you having no means to find out if actual data is compromised.

 

[brutalizer]

As far as I know, ZFS was the first common solution to do this. ZFS initializes in the background as needed. Nice to see this feature spreading to other solutions too.