On Friday, December 8, 2017 12:48:45 AM CET Wols Lists wrote: > On 07/12/17 22:35, Frank Steinmetzger wrote: > >> (Oh - and md raid-5/6 also mix data and parity, so the same holds true > >> > >> > there.) > > > > Ok, wasn’t aware of that. I thought I read in a ZFS article that this were > > a special thing. > > Say you've got a four-drive raid-6, it'll be something like > > data1 data2 parity1 parity2 > data3 parity3 parity4 data4 > parity5 parity6 data5 data6 > > The only thing to watch out for (and zfs is likely the same) if a file > fits inside a single chunk it will be recoverable from a single drive. > And I think chunks can be anything up to 64MB.
Except that ZFS doesn't have fixed on-disk-chunk-sizes. (especially if you use compression) See: https://www.delphix.com/blog/delphix-engineering/zfs-raidz-stripe-width-or-how-i-learned-stop-worrying-and-love-raidz -- Joost
