cancel
Showing results for 
Search instead for 
Did you mean: 

What type of raid should I use?

Erik98
Level 7
Hi!

I want to use a RAID that functions like this: 2 SSD's in RAID 0 so it'll be ~1TB SSD and 1/2 1TB S-ATA 6GB/s drive(s) for copying exactly what the SSD's are writing.

Please help me, I want this in my system 😞
4,833 Views
2 REPLIES 2

HiVizMan
Level 40
Hello my friend.



If I have understood you correctly you wish to RAID a SSD and a mechanical hard drive.

I would strongly suggest you do not go that route. The SSD alone is way faster. The RAID would not benefit you at all.

What you can do to protect your system is have a daily back up of your SSD, there are some great programs out in freeware land that will do a exact copy. The first time will take a long time as it is writing the entire SSD. But there after each day only the changes are written to the back up.

If I have not understood correctly please advice me so we can work out a solution for you. 🙂
To help us help you - please provide as much information about your system and the problem as possible.

nleksan
Level 10
I think he is basically saying he wants a RAID01, with one striped set being SSD's and the other being spinny drives.

That won't work, and wouldn't be a good idea even if it did, as you're ALWAYS bottlenecked by the SLOWEST DRIVE in an array.


That said, I'd forego the SSD Array, quite frankly you only need one and getting a platter array to match the SSD for sequential throughput WILL require a (not inexpensive) hardware RAID HBA (RAID Controller Card), not cheap pseudo-RAID cards like Highpoint/Promise, but the real deal like any newer Adaptec/LSI/Areca/3ware models, ideally with 8-16 drive support and at least 1GB of onboard cache.
Then, you'd need the mechanical drives that can sustain those kind of data transfer rates, which fortunately as of right now is rather inexpensive, with the Western Digital Blue 1TB WD10EZEX capable of up to 210MB/sec at the outside of the platter.

I personally have a number of hardware based arrays, using:
Areca ARC-1882ix-24-4GNC 4GB with an Intel SAS Expander for a total of 29 mechanical drives
2 H800's, 3 PERC(5/i and 6/i), 2 M1015, and 2 M5015 (all are re-branded models of LSI/etc cards)
Recently got a new 16-port Adaptec Series 7 PCIe 3.0 x8 card as well as one of their 12GB/sec models, but haven't yet gotten the drives with the 12GB/s SAS interface.

You will want something like an LSI SAS9261-8i or better, 4-6x WD10EZEX or Seagate Barracuda 7200.14 1-3TB (the 1TB/platter ones) in RAID0, but keep in mind that one drive has issues, they ALL have issues....

Should you really want to do an SSD RAID0 setup, despite there being zero real world benefits (SSD's don't scale random 4K IOPS, they scale sequentially; the thing is, SSD's are so fast because of their super low access times, as well as their random 4K IOPS...not their sequential speeds).....you're looking at around 8x drives, minimum, and with 8 you'd have to short-stroke them so as not to choke up the transfers once you hit the inner half of the platters.



Honestly, for most people, RAID is an expensive but ultimately far from useful endeavor. It's going to cost you money and a lot of time to keep up an array, although with RAID0 you'll lose EVERYTHING the second one drive fails,so I guess it's less of an issue there....

Fun to play around with, but unless you have a fair amount of experience running multiple arrays 24/7 (and not just RAID0, which is not really even RAID....no redundancy; RAID5/5E/6/50/60/etc require a lot more knowledge but the benefits are greater, as you can have an almost zero-downtime storage solution if done right), I would NOT recommend starting with all your data on two RAID0 arrays.

If you're streaming, a few SEPARATE WD10EZEX or 7200.14's is more than enough, as each will write 1080p60 across most if not all of the platter.

Lastly, don't stream to your SSD; it's a huge amount of completely unnecessary wear, and in fact, SSD's aren't nearly as good as HDD's for sustained sequential tasks.