ssd - Implementing raid-1 with solid state drives
2014-07
Sidney
So, I was recently hired on to a company that has shipped out several 24/7 always on servers.. With solid state drives. I understand that SSD longevity has been improved upon, however to my knowledge the drives are not going to last the length of time some of our clients want them too (10+ years in the worst cases), whereas conventional hard drives would. The company I am part of decided to do this, and implemented RAID 1 as a data integrity fail safe, which I have no argument against; id recommend it for solid state or conventional drives.
I am concerned about the fact that while HDD failures are usually due to mechanical issues and thus are not particularly predictable, whereas with SSD's, failures are more likely to be due to the number of read-write cycles being used and thus are fairly predictable. Considering that the two drives in each computer would be an identical mirror (and probably have an identical read write history) what are the odds that the drives would fail within a short period of time?
Just a note, I'm gonna take a random guess that in the way we order (two drives at the same time) It's pretty likely that we'd get two consecutively manufactured devices, so they would be manufactured under identical conditions, so I would think their max read/write cycles would be pretty similar.
Kato
For something like Final Cut Pro where you have scratch disks, is it absolutely a bad idea to use a solid state drive? There would be a lot of writing, but I'm thinking it would be less for video editing then say, programming? The read/write cycles for SSDs still seem pretty long...
Joey
With normal usage a SSD nowadays survives about as long as a hard drive. Or so vendors tell us. So the write cycle thing should be sufficient for anything you attempt and wear-leveling causes writes to appear all over the SSD instead of hot spots.
And scratch disks aren't that different from normal temporary file usage or the page file for example. Both haven't killed my SSD so far.
James Tisato
Intel's wear-leveling algorithms are that good that they guarantee that you can write 100GB per day for 5 years without loss of data. That would suggest that using one as a scratch disk would be just fine and would certainly boost your system's performance.