[Rick Lang]

Dave, looking at the mapping of port numbers in the article Jeremy linked to, please specify the port numbers for each device. When your post mentioned “lower” were primary, it’s not clear (at least to me). Thanks.

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

I believe I saw that R8 performance was even faster than R6 if that is a concern. Also enable pre-fetching to improve video READ performance. Copied from the Promise Knowledge Base 10394:

How to bench mark Pegasus2 R8
There are several bench tools out there among them are Black Magic Disk Speed Test and AJA System Tests.

These tools are ok to gauge basic throughput. Before you begin your benchmark testing we recommend to enable the aggressive pre-fetching AKA “controller forced read ahead” on your Pegasus2.

Promise plans to enable controller forced read ahead by default in the upcoming service release.

NOTE: Controller forced read ahead is most beneficial if you are working with Audio and Video files where the IO access is large block sequential IO.
Small block random IO will not benefit from this setting.

How to enable controller forced read using Promise CLI:

1. Login using your Administrator and from a terminal in your Mac host type “promiseutil”

2. From our CLI type: ctrl -a mod -i 1 -s “forcedreadahead=enable”

3. Confirm the setting is now enabled issuing the following command: ctrl -v

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

Thanks, Jeremy. I’m going to take your advice and stay with a ProRes workflow. Makes everything manageable.

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

Jeremy, you are correct that normally ProRes 4:2:2 HQ would be the codec of choice and that’s about 110 MB/s (884 Mbps) for 4K work if memory serves me correctly. I was curious what impact uncompressed video would be though to see if that was even feasible on the Pegasus2 R6. It appears it may be possible looking at the numbers but I’ve no experience with 4K, ergo my post.

I know an 8-bay will handle it, but that starts to get expensive. A Pegasus2 R4 in RAID 0 might as well but I hope to avoid that temptation and have the data redundancy of RAID 5 or 6. I remember someone advising to steer clear of a 6-bay configuration, but I’m not aware of the rationale for that warning. Perhaps it was just that RAID 6 on an 8-bay is the best insurance and performance.

Thanks for your advice re the calculator as I had forgotten that. I’ll pick that up now.

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

Further to John’s observations about the speed of the internal SSDs, MacWorld just published their benchmark of the new Pegasus2 R6, on a Mac Pro using RAID 5:

Drive Black Magic Write Black Magic Read
Pegasus2 R6 (7200-rpm hard drives) 833 742 MB/s

Looking at Wikipedia:
The storage and data rates for the widely used YCbCr 4:2:2 chroma subsampling uncompressed video are listed below:

1080i and 1080p HDTV uncompressed
8 bit @ 1920 x 1080 @ 24fps = 95 MB per/sec, or 334 GB per/hr.
10 bit @ 1920 x 1080 @ 24fps = 127 MB per/sec, or 445 GB per/hr.

8 bit @ 1920 x 1080 @ 25fps = 99 MB per/sec, or 348 GB per/hr.
10 bit @ 1920 x 1080 @ 25fps = 132 MB per/sec, or 463 GB per/hr.

8 bit @ 1920 x 1080 @ 29.97fps = 119 MB per/sec, or 417 GB per/hr.
10 bit @ 1920 x 1080 @ 29.97fps = 158 MB per/sec, or 556 GB per/hr.

Clearly HD is not a concern for very short duration work, but when you quadruple it for 4K (UHD) data rates:
10 bit @ 3840 x 2160 @ 29.97fps = 624 MB per/sec, or 2224 GB per/hr.

Clearly one isn’t going to use the internal flash for storage of 4K video, but are the Pegasus2 write and read speeds going to provide a comfortable performance margin for 4K workflows? Or is an 8-bay RAID 5/6, the preferred and highly recommended option? Thanks for any comment you may have.

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

Thanks, Craig. Would you also recommend using the x264 QT plug-in? According to that article, it produced even better results.

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

Didn’t find any XML support but it mentioned you could open the project in Vegas…

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

Franz, the Larry Jordan blog is interesting in how he comes to his conclusions. At the end of the article he clearly advises that the iMac may make the most sense if you do a lot of work in Compressor. But before you get to his conclusion, he equally clearly states that the gain for the iMac occurs due to the QuickSync feature for video hardware acceleration found in the iMac [and the MacBook Pro as I recall] which is only active for a single pass compression. He clearly shows the high-end Mac Pro beating the iMac for multi-pass compression! If I was Larry, and I wrote this conclusion, I’d be embarrassed to see I forgot to add ” for single-pass compression.”

How relevant is his finding? You be the judge, but I’m an amateur and I never do a single-pass when I have an option for better quality; I take the option that provides the best I can do, not the fastest. No deadlines luckily.

It is still early in terms of many people writing about their own experiences using the new Mac Pro. We are getting a better understanding of strengths and weaknesses. Over the next months, we shall all have a better understanding than what we had in the first week of the machine being available.

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

I didn’t see any flavour of ProRes listed in the supported file types. (And no HDV.)

Rick Lang

iMac 27” 2.8GHz i7 16GB

[Rick Lang]

I believe Dave Girard’s review said the Apple FirePro included 10-bit colour but since OS X doesn’t support 10-bit colour yet, you can utilize the 10-bit colour if you boot up under Windows.

I think that was a very detailed review from a perspective (visual effects artists) of which I have very limited understanding. Once in a while I thought he was even contradicting himself but I guess that’s inevitable in such a lengthy review. I really appreciated the effort made in that review but it seemed flawed at times and selective of things that didn’t show off the Mac Pro in its best light.

I hesitate to give examples because I don’t want to get into a fight about my opinion versus anyone else’s opinion, but one example would be the number of times he used Cinebench 11.5 tests when he probably knows Cinebench 15 results would show better performance. He also repeatedly played down the FirePro label (workstation class GPU) and referred to it as the gamers 7970 I think. Why would he do that after educating us in the distinction between Intel desktop machines that may be faster than the Xeon, but point out the much more rigorous testing the workstation Xeons must pass? Just because some of the physical specs are similar to the gamers GPU, doesn’t mean that Apple GPUs were not subjected to similar rigorous testing befitting a workstation GPU.

It is a superb review overall and paired with the AnandTech review that emphasizes other aspects, these reviews give a rather good picture of the new Mac Pro. Considering how superficial many of the reviews have been, I hope Apple reads the Girard review carefully and thoughtfully. I don’t see the new Mac Pro and the software running on it as immutable. It seems to me it may take months or even a few years as software and hardware evolve for the combination to be a winner for more disciplines. Right now is just that, the present. Who knows what will happen tomorrow. If you are primarily a user of Final Cut X and DaVinci Resolve, at least today you should have a good night’s sleep! And bless you all.

Rick Lang

iMac 27” 2.8GHz i7 16GB