[rescue] Sun 711

[Joshua D Boyd]

On Thu, May 02, 2002 at 01:54:19AM +0100, Chris Byrne wrote:
> Okay, I just read the HDBOXX spec sheet and there is no way in hell they are
> streaming 300MB/s. They have a single dual channel U160 controller on a
> single PCI bus. Since they don't mention it as a feature, Im going to guess
> its a 32 bit 33 mhz bus. The MAXIMUM theoretical limit of a 32 bit 33 mhz
> bus is 125MB per second.
> 
> And its going in to 10 drvies. Split over the two channels that's five
> drives per channel which means once again nbo way are they sustaining
> 300MB/s
> 
> They are saying that they have 360gb capacity for appx 50 minutes. Thats 7
> or so GB per minute which is only 116MB/s

The thing about the HDBOXX is that they mainly advertise HD throughput, not 
2k resolution.

So, the HDBOXX really only needs 142M/s (not taking into account 
avi/qt/tiff/whatever overhead) most of the time.

They do also advertise 2k in a 1.77 aspect ratio.  So, that is... 
(* 2048 1556 3 24 (/ 1 1024.0) (/ 1.0 1024))
218megs per second.  So, it only needs to use about 68% of the advertised
SCSI bandwidth, which should be do-able.  Again, that isn't taking into
account possible overhead from the fileformat and file system.

Despite not shouting it out, this machine does use PCI66/64, BTW.

-- 
Joshua D. Boyd