Originally Posted by
drissa
I currently have a second drive in my Mac Pro for video files. This is full and I feel it's time for a better solution. I've been investigating software RAID - possibly RAID 10. I understand this doesn't provide back-up, but I'm interested in drive redundancy, speed benefits, etc.
I don't need 100% peace of mind - eg. off-site backups.
[Note: below comments are addressed at a single-user single-MP operation, 4-5 internal drives and video/still images work; specifically
not at large arrays, large DBs, financial operations, etc.]
Anything with RAID1 in it is hugely inefficient just to gain real-time redundancy when a drive fails. What are your real needs? If you do not really need real-time redundancy RAID0 is twice as efficient (but with concurrent higher risk of array failure). Workflow failures are common in images work (my guess would be >100x more common than unexpected drive failures), and
when a workflow fails (e.g. corrupted file, application or OS) RAID1 mirror solutions like RAID10 instantly replicate the failure across the array. For
images work IMO it is far better to implement non-real-time backup routines that occur at times when we reasonably believe that what we are backing up is uncorrupted.
If for instance the original video files exist elsewhere and the array is just part of the workflow most times a proper backup strategy can be created that cost-effectively covers the case of catastrophic drive failure.
Drive fullness is an important characteristic of HDD throughput, so IMO design drive capacities around running performance operations at 50% full. In my pre-SSD MP bay1 was OS/apps, bays 2/3 working image files RAID0 <50% full, bay 4 on site backup 85% full. I used Apple's software RAID and it worked fine, but a (pricey) hardware RAID controller would have been much better.
Today I cannot imagine a workflow without SSD; the impact of SSD on operations where latency is significant is beyond stunning. I suggest looking carefully at the workflow and see where SSD may be beneficial and plan accordingly. In my case for instance the image files are stored on external HDDs but the working Library that references the HDDs lives on SSD; it depends on the workflow. Certainly like mduell said, as a minimum stick an SSD in the 2nd optical drive bay for boot and apps.
In any event, IMO in single-user images work real-time redundancy like RAID10 is usually an inappropriate waste of drive bays and drives.
HTH
-Allen