5 May
2010
5 May
'10
10:39 a.m.
Arnold,
Here is my advice:
Don't do hardware-raid! Neither the real nor the "soft" hardware raid help
you
that much. What do you do when the controller fails?
Well, this is a stupid advice, unless you tell plutek also to get
everything else in his studio twice.
A hardware raid does all the computation for you and just passes along
the data you need. It also eats away a lot of stress through huge
buffers. With an Areca 1280 for example, I get 3GB/s for the first
second and ~1.5GB/s sustained on a RAID6.
With software raid, you have to transfer all data twice through the
system, you fuck up you caches, and the CPU has to do all the
computations. If you only have two drives, it doesn't matter that much.
So it really depends on what you want to do and what your budget is. If
you have to avoid IO stress, go and get a decent RAID controller.
With a hardware-raid you have to have a second of the
same kind in stock to
get back the data on your disks. Don't even think about not having a spare
controller and buying one when yours fails.
This is only true if the on-disk format is not specified somewhere. If
you buy cheap shit, that may be and you may have to fiddle around to
extract the data. But it can be done.
The "reduced" throughput of a software-raid
is worth the ease of use. And its
not that "reduced" at all.
Again, it depends on the use case.
Oh, and use only raid1 or combinations of 0 and 1. For
all the others see
http://baarf.com.
Again, it depends on the use case. As a general rule, this is just wrong.
Flo
--
Machines can do the work, so people have time to think.
public key DA43FEF4 x-hkp://wwwkeys.eu.pgp.net