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[zfs-discuss] Basic question about striping and ZFS

Subject: [zfs-discuss] Basic question about striping and ZFS
From: Ilya
Date: Wed, 04 Nov 2009 17:00:22 PST
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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