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Researching about ZFS and had a question leating to Raid-Z and the striping.
So, I was glacing over Jeff's blog (http://blogs.sun.com/bonwick/entry/raid_z):
[i]"RAID-Z is a data/parity scheme like RAID-5, but it uses dynamic stripe
width. Every block is its own RAID-Z stripe, regardless of blocksize. This
means that every RAID-Z write is a full-stripe write. This, when combined with
the copy-on-write transactional semantics of ZFS, completely eliminates the
RAID write hole. RAID-Z is also faster than traditional RAID because it never
has to do read-modify-write. "[/i]
So firstly, is this literally referring to the blocks of a file for example?
Also by stripe, is this referring to the stripe UNITS (within a whole stripe)
or the ENTIRE stripe across disks?
So, let's say that you have a file of 64 kb per sector (stripe units consisting
of blocks of whatever size totaling 64k) across four disks.
Disk 0: Stripe 1
Disk 1: Stripe 2
Disk 2: Stripe 3
Disk 3: Parity
When Jeff's blog mentions that "every block has it's own stripe" what does he
exactly mean in the context of this example? And let's say that I am
modifying/write out bytes in the first stripe, how does this affect the other
stripes/parity?
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