On Sun, Dec 16, 2007 at 01:10:21PM -0800, Bob La Quey wrote:
So the issue boils down to which, hardware or software, one believes is better and why. I am falling into the ZFS (let the software do it) camp. My reasoning is that this will be faster, cheaper, and just generally better in the (slightly) long run. The real progress from Moore's law is taking us toward more cpus per chip. Let's use some of that horsepower to drive ZFS and ZFS-like systems that have data integrity built into them from the get go.
So far, I'm seeing the main disadvantage of software RAID is that it is more difficult to coordinate cache synchronization between separate drives. Good HW raid controllers will have battery-backed RAM that can keep the cache alive across a power-failure and avoid having inconsistent data between drives. This can be done in SW raid, but requires a full cache synchronization, which can cause performance degredation. ZFS claims they've eliminated the need for this, but Jeff's blog still says that they use a cache synchronize operation, so I don't see how it is any better. Dave -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
