Looking for RAID Drivers

[Mark Haney]

Elizabeth Bevilacqua wrote:
> On Fri, Sep 19, 2008 at 10:08 PM, John Hubbard <ender8282 at yahoo.com> wrote:
>> Linux implements its own software raid.  True hardware
>> raid is pretty expensive and not very common.  Unless you spent a good
>> chunk of cash on your board, I would guess it is actually software raid.
> 
> And lest you get concerned about spending money on this card and not
> being able to use it for RAID - benchmarks have shown that Linux
> software RAID is faster than most of the RAID cards you can buy. So
> you'll still be making out fine (or better!) by using the controller
> as simply an SATA controller and then using Linux software RAID.
> 

I'd REALLY like to see those benchmarks.  Because I simply don't believe 
it.  Sure, the linux dm-raid is damn good, but nothing beats having a 
controller do the 'package and assembly' work for you off-CPU.  In a 
resource intensive setup S/W RAID can't cut it, except for maybe (and I 
emphasize MAYBE with Reads).

When you can offload the work to a dedicated controller you free up the 
CPU for other processes.  The kernel doesn't know or care about the RAID 
functions at that point and can concentrate on what it does best.  Not 
to mention, as per my previous post, that the S/W RAID setup is still 
not as stable as I would like.  And, even on RAID 5 the likelihood you 
lose data is increased with S/W RAID if a drive fails.


-- 
Libenter homines id quod volunt credunt -- Caius Julius Caesar


Mark Haney
Sr. Systems Administrator
ERC Broadband
(828) 350-2415

Call (866) ERC-7110 for after hours support