> On Wed, 8 Jul 2009, Moore, Joe wrote:
> That's true for the worst case, but zfs mitigates
> that somewhat by
> batching i/o into a transaction group. This means
> that i/o is done every
> 30 seconds (or 5 seconds, depending on the version
> you're running),
> allowing multiple writes to be wr
> Do you have data to back this up?
It's more of a logical observation. The random data corruption I've had up
through the years have generally either involved a single sector or two or a
full disk failure. 5% parity on a 128KB block size would allow you to lose
6.4KB, or ~10 512 byte sectors.
> You are describing the copies parameter. It really
> helps to describe
> it in pictures, rather than words. So I did that.
> http://blogs.sun.com/relling/entry/zfs_copies_and_data
> _protection
> -- richard
It's not quite like copies as it's not actually a copy of the data I'm talking
about.
ZFS is able to detect corruption thanks to checksumming, but for single drives
(regular folk-pcs) it doesn't help much unless it can correct them. I've been
searching and can't find anything on the topic, so here goes:
1. Can ZFS do parity data on a single drive? e.g. x% parity for all writes,
