HD Playback on Catalyst

[OlliR]

i think - from my testing - you are wasting the power of your computer with your sata RAID.
I can get 7 layers with my MTRON SSD. same computer.
you do have x1900?
You need x1900 at these resolutions 7300 has very poor performance at hi-def sizes

I have the X1900.

I did the test you suggested. Though not unraiding the disks but copying the test files folder to the system disk.

Same result 3 layers with 1920x1080 playback at 25fps.
Layer 4 plays back just below 25 fps.

So the RAID seems to be no advantage at all. I did not expect this. I believed the RAID should have a greater bandwidth and perform better with larger files.

For sure I will look into the MTRON SSDs. But 1500 Euros for 64 GB is quite a statement...

[samsc]

So the RAID seems to be no advantage at all. I did not expect this. I believed the RAID should have a greater bandwidth and perform better with larger files.

For sure I will look into the MTRON SSDs. But 1500 Euros for 64 GB is quite a statement...

raids do not work - and are pointless unless you are trying to achieve high data rates - with only 2 or 3 layers for uncompressed playback -
other than that they are pointless. I keep trying to say this-

the problem is that SATA discs have very poor random access data rates - sure they can do 150MB/s or more in a RAID config- but that is for 1 file - read sequentially.
catalyst does not read 1 file sequentially. It reads 1 file for each and every layer. In a random and unpredictable manner.
And SATA raids can actually perform worse with catalyst than a single disc.
A hard disc is a rotating device that typically rotates at 7200rpm - one revolution in 8.3ms - only a single read head - if you miss the data you need on one rotation - you have to wait up to another 8.33ms before it comes round again. 8.33ms is forever in computers.

The MTRON discs are worth every single cent - you get up to 14 layers of playback - with no dropped frames - on any layers - because there is no rotational latency - access times are 0.1ms -
Being able to almost guarantee this performance across all files - at all times - in the type of shows we do - is a life saver.
Performance is critical in almost all the shows i do.
As it is in most video applications.

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Did you find a source for the MTRON discs in the EU?
for 6 1080p layers rather than 3 1080p layers - double the performance - i dont think the cost is much.

[jjrecort]

the problem is that SATA discs have very poor random access data rates - sure they can do 150MB/s or more in a RAID config- but that is for 1 file - read sequentially.
catalyst does not read 1 file sequentially. It reads 1 file for each and every layer. In a random and unpredictable manner.
And SATA raids can actually perform worse with catalyst than a single

But What about WD RAPTORS..are SATA but with the same specs of the SCSI.. 10.000 rpm and

- Read Seek Time 4.6 ms
- Write Seek Time 5.2 ms (average)
- Track-To-Track Seek Time 0.4 ms (average)

The problem is when we have to move HD files.. we need both.. high output and high access speed!

[samsc]

But What about WD RAPTORS..are SATA but with the same specs of the SCSI.. 10.000 rpm and

- Read Seek Time 4.6 ms
- Write Seek Time 5.2 ms (average)
- Track-To-Track Seek Time 0.4 ms (average)

The problem is when we have to move HD files.. we need both.. high output and high access speed!

raptors do not work as well as scsi.

Use MTRON SSD. works much better

[samsc]

Same result 3 layers with 1920x1080 playback at 25fps.
Layer 4 plays back just below 25 fps.

and you cant get more than 3 layers off these discs- whatever you do- ( and its worse with ntsc which needs 30fps )
- unless you have a huge buffer- or complex caching strategy.
And amazingly enough - this hasnt changed much in the 5 years since v3 started.

You might like to try a single Raptor 150GB drive- and see what you get?
though they arent that much better.

you should also - in most applications - never use the system disc - because the system disc is used for the virtual memory cache.
and the os when it accesses this - will interfere with playback.