ZFS raid write performance?

[Xin Li]

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On 06/22/15 05:13, kpneal at pobox.com wrote:
> For both reads and writes all levels of raidz* perform slightly
> faster than the speed of a single drive. _Slightly_ faster, like,
> the speed of a single drive * 1.1 or so roughly speaking.

How big is the data block for each read-write?  For large blocks
RAID-Z is likely to perform nearly as well as stripped disks (e.g. 3
disks RAID-Z is slightly slower than 2 disk stripped, but would be
much better than single disk pool).  Typically copying data would use
larger data blocks.

For smaller writes it's likely to have worse results.

> Finally, single GigE is _slow_. I see no point in a "landing pad"
> when using unbonded GigE.

How will a "landing pad" help when let's say we have 10GigE or even
faster network connection?

Cheers,
- -- 
Xin LI <delphij at delphij.net>    https://www.delphij.net/
FreeBSD - The Power to Serve!           Live free or die
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