Hardware for serving lot's of Raster

[Ken Lord]

I happily stand corrected,  thanks for the information Shawn.

Cheers,
Ken Lord
Vancouver BC

On 11/20/05, Shawn Wallbridge <shawn at synack-hosting.com> wrote:
> On 20-Nov-05, at 11:07 PM, Ken Lord wrote:
>
> > Hi Shoaib, Ed,
>
> <snip>
>
> >   IDE RAID is still limited to the
> > 133Mb/s IDE bandwidth limit,  the more drives you add, the more you
> > will hit the bandwidth limit.
>
> I would like to comment on this one portion, everything else was
> excellent information.
>
> The bandwidth limit of an IDE RAID controller varies GREATLY depending
> on the design. Low end 'consumer' IDE 'RAID' controllers like the
> cheaper Promise controllers are limited because a) they are software
> based, so the CPU handles all the RAID functionality and b) they tend
> to use multiple drives per IDE channel. The higher end cards like the
> 3Ware (my favourite) or the Adaptec controllers are vastly different,
> they use one drive per channel (so their is no contention) and use
> dedicated processors for the parity calculations instead of the CPU. If
> you set up a RAID 0 array (not that that is _really_ raid) you would be
> able to get much much more than 133Mb/s out of a _real_ raid
> controller.
>
> I have about 8TB of data on 3Ware 750x series IDE controllers and they
> perform very well. I also have about 8TB of data on 3Ware 950x S-ATA
> controllers and they also perform well. I am looking forward to
> building a new server with the 9550SX series S-ATA II controller.
>
> <snip>
>
> shawn
>