I found an very interesting load on information based on Windows machines but the topic "Premiere storage concepts" here:
http://ppbm7.com/index.php/tweakers-page/84-disk-setup/95-disk-setup
I agree to your advise not to use a striped raid on the boot volume. It does not help editing performance, only doubles the risk of catastrophic data loss.
To be honest, i have to break a "dont's rule" for this video editing machine by installing non-video related software on an editing machine, like an Office suite and probably a few games since this will be my only one desktop.
Yes i planned with an external NAS, probably also two some months later when i finished this project.
One NAS as the primary system and film+photo file backup solution based on Gigabit RJ-45. For now i don't know if RAID 5 or 10 and i haven't thought about to overall netto capacity. Just a hint, i saw that the logic board has an external USB 3.1 port if i'm right. But i think Gigabit Ethernet is just ok for this usage.
Maybe a 2nd small NAS just as a data grave directly attached via USB* to the system (i'll come later back again on this).
My gear is a Sony FS700RH and a Sony A7S. An external recorder like an Atomos Inferno or a CD 7Q+ for UHD/4K DCI will come.
Codecs like AVCHD, XAVC, ProRes and maybe some GoPro stuff will be used which are all disk & CPU/memory intensive according to the codec table shown in this link.
For now it's just 1080P and UHD. But 4k DCI will come when i buy an external recorder.
Based on the linked article (Practical disk setup and Guidelines of disk usage) i thought on this internal storage concepts:
(i think it can be somehow adapted for all kinds of NLEs like Premiere/AE, FCPX and Lightroom somehow with it's database)
All based on internal SATA 6G drives
C1. 3 disks +1
SSD OS+Applications -> 250 or 500GB
HDD Media, Projects -> 2TB
SSD Previews, Media cache, Exports -> 500GB
HDD Data grave for daily stuff like downloads and all other junk 2 TB to cancel the 2nd NAS
C2. 4 disks +1
SSD OS+Applications -> 250 or 500GB
HDD Media, Projects -> 2TB
SSD Media cache -> 500GB
SSD Previews, Exports -> 250GB
HDD Data grave for daily stuff like downloads and all other junk 2 TB to cancel the 2nd NAS
I thought on C1 and C2 to choose a 250GB SSD for Media and Projects. But i fear this wouldn't be enough space when i start to use external recorder footage. So i don't know if this HDD according to the information below could be a bottleneck?
You're welcome to correct me if the HDD/SSD combos and the size doesn't make sense.
I've chosen this depending on this...
The kind of files used during editing are, in order of their need for speed:
- Media cache & Media cache database files, created on importing media into a project. They contain indexed, conformed audio and peak files for waveform display.
Typically small files, but lots of them, so in the end they still occupy lots of disk space.
- Preview (rendered) files, created when the time-line is rendered for preview purposes, the red bar turned to green. Read all the time when previewing the time-line.
- Project files, including project auto-save files, that are constantly being read and saved as auto-save files and written when saving your edits.
- Media files, the original video material ingested from tape or card based cameras. Typically long files, only used for reading, since PR is a non-destructive editor.
- Export files, created when the time-line is exported to its final delivery format. These files are typically only written once and often vary in size from several hundred KB to tens of GB.
When you are doubting which category of files to put on which kind of disk, especially when using both SSD's and HDD's, keep in mind that the speed advantage of SSD's over HDD's is most noteworthy with the Media cache & Media cache database. These files are frequently accessed, are small and there are many, so reducing latency and seek times and increasing transfer rates pays off by putting these on a SSD, rather than on a HDD, even if it is a raid0. Export files can go to the slowest volume on your system, since you only export once. To help you decide, I have added priority rank-numbers for speed, with 1 for the fastest volume and 5 for the least speed-demanding category.
What happens when you have less than 6 disks / volumes? You combine certain files types on the same volume, for instance
project files and
export files on the same volume. That entails a higher fill rate on that volume and thus more 'fill rate' degradation, lowering the sustained transfer rate on that volume. In addition the overhead from the OS increases, because the Windows house-keeping tasks, like updating file allocation tables and access and modification time-stamps for each file used, increases due to the extra number of modified files. Of course the main bottleneck still is the half-duplex problem, waiting for reading to finish before writing can occur and vice versa.
Why did I use
project and
export files to be combined in the example above? Because the project files are relatively small, as are the export files, so when you combine them on a single volume the performance degradation from 'fill-rate' is relatively small, especially if you consider that on writing the export files to the volume, the project file is no longer accessed. The work has already been done. An alternative approach might be to combine Media Cache, Previews and Exports on the same volume, because Previews are not used during Export nor is Media Cache, so Exports are the only (write) activity on this volume. These kind of considerations ripple through to the table below, which shows how one could allocate the various type of files to the available disks or volumes.
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) the lessons from older approaches still work:
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