Stream Counts on FC XSan?

Hello Cow forum readers,

Are there any XSan users/owners out there that can confirm some Fibre Channel connectivity/performance benchmarks for me?

We are looking at a creating a 9 camera capture for live events and need fast turnaround multi-cam editing. We have the capture side covered, but in our team there is some doubt as to what the actual realtime editing performance of the current MacPro systems actually is and I can't seem to find any specs on this on the web.

Before going down the path of an offline/online process as a workaround, i want to know what is and isn't possible using XSan and a MacPro.

Even over such a large bandwidth as is available over Fibre Channel storage, I know for instance that an Avid Media Composer with an 8Gb Fibre card cannot do more than 4-5 streams of DnXHD 220Mb/s on a single MacPro due to CPU performance limitations. This is just over 1Gb/s on a 8Gb/s pipe, so there is big pipe with only a trickle coming down it due to the limits of today's Mac and WIN CPUs.

In this case my client wants to use FCP, so I am trying to determine what sort of stream counts I can reliably play in a single Final Cut Pro client running single (or dual 4Gb) Fibre Channel card. This would be a late model MacPro workstation; I may need a few workstations working on segments to achieve the desired turnaround, so a collaborative approach is required on this job, hence the need for Xsan or some other solution that supports FCP with multicam performance on each workstation.

So, assuming I am using an Xsan system (not just a direct attached Xraid) with enough drives to support any of the following, and a suitably equipped MacPro with FC card, then :

- how many FCP realtime multicam streams at ProRes HQ (HD 422/ 220Mb/s) ? if I cant get 9 , what is the cut off number over FibreChannel?

-if I can't achieve 9 stream multicam in the above, what is the suggested HD resolutions I need to work with to achieve 9 streams in realtime for HD?

and just for interest (we dont need it but would be good to know):

- if using ProRes 444, how many can I get in the same scenario? What is the cut off number over Fibre Channel?



Hopefully there is someone out there actually doing this so I can get accurate numbers.

Thanks to all in advance.

Paul Hayes
Australia