Some RAID advice requested

[lewisanderson]

Good day,

I'll be doing my next build hopefully this summer and I'm going for an NVMe m.2 drive as my boot drive. That's fine, but I'd like to try and ditch HDDs altogether and use the two SATA SSDs I have already.

I've got one Samsung 840 Evo thats 250 GB
I've also got a Crucial BX300 which is 960 GB

Even though I'm no stranger to building, I've never looked into RAID before and I was wondering if I could ask the community a couple of questions.

1. Can I RAID these two drives? Would I get an unexpected result?
2. Is it as straightforward as linking them and getting over 1TB of space at double the speed?
3. Do I need any additional parts/equipment/cables to actually link them?
4. If it is possible, would it be worth it in this scenario?

Forgive my confusion on RAID, I've been meaning to look into it for a while but I've never gotten round to doing it 😛

Thanks,
-Lewis

 

[atljsf]

these drives are not the same size

raid asks you for two exact same size units

perhaps you can make the 960 gbs one to work at 250gbs, not sure if that works

raid on sata is meant to join two slow hard disk and get decent speeds under the sata limits they are not reaching

raid two ssds, well, they mostly will reach the sata limit alone, not sure what resutls can you get here when using raid

do you want to jint them to get a single volume bigger? or just raid to make a mirror of the other one?

 

[alceryes]

You *may* be able to RAID them. It depends on the controller you use. If you are talking about using the MB RAID setup then I don't know, MB controllers aren't known for being super robust. At best, the 960GB would be reduced to a 250GB drive for the purpose of the RAID.
If you want to use an external NAS then you'll have better luck as some of those use advanced (usually proprietary) RAID schemes to just group all your drives into one big pool. Even with that there are limitations though.
RAID setup can be easy but it's not THAT straightforward. It sounds like you are talking about RAID 0 (striping). No, you don't get double the speed and in some instances you may even lose performance.
Your best/easiest solution is forgo the RAID and either use them as 2 separate drives or span/stripe the drives in Windows. http://www.windowscentral.com/how-create-one-large-volume-using-multiple-hard-drives-windows-10

 

[boosted1g]

1) you can only RAID drives that are the same size. You can "pool" the drives together to make it appear as one large drive but there is really no bennefit to this

2 & 3) Most motherbaords have the ability for at least RAID 0,1,0+1 so it is simply a matter of plugging them into the motherboard's sata ports, setting those ports to RAID mode and configuring the array

4) There is pretty much no noticable performance gain by putting SSD drives into RAID. You are still restricted to the seek time of teh SSD, the max read/write is not the bottleneck.

5) RAID 0 in theory provides you with double max speed but also provies you with double the data loss percentage, if one drive dies in raid 0 then you loose ALL of the data on both drives as half of the file is one drive and half on the other.

RAID 1 is nearly pointless in a home environment. Businesses use RAID 1 to have an immeidate hot-swap backup to their revenue critical Server's OS in case of a disk failure. Now these businesses also realized the limitation of RAID 1 and thus have other backups as well.
Somewhere down the road though there was a large misconseption by the masses that RAID 1= a backup which is completely not true. RAID 1 is a mirror, a perfect copy; thus if say a windows update trashes your system and you cant boot, with RAID 1 you have a useless percect copy of the same screwed up OS; clearly this is not the same thing as a backup.

 

[Paperdoc]

First point, already mentioned at least twice, is that RAID0 is meant to allow faster performance using two drives because of the seek time delay in a mechanical drive. But SSD's are SO MUCH faster than any mechanical drive, there is almost NO speed advantage to using RAID0 with them.

As others have said, putting those two units into a RAID0 or RAID1 array will LOSE a huge chunk of your space! Both of those RAID systems will default to limiting the larger unit in a mismatched pair to the capacity of the smaller one.

You will get maximum capacity if you simply use those two SSD's as separate storage devices.

There is ONE way you can combine them to appear to be one drive. It is called JBOD ("Just a Bunch of Disks") and requires that you use a device driver that hides the process of using both devices as if they were one combo. Very often that driver is included with RAID drivers, so sometimes people think of JBOD as another version of RAID, but it is not. However, I'm not sure what effect using JBOD has on speed of data access. PLUS, you should realize if you use that system, there is no universal "standard" for that (just as there is no standard for RAID), so trying to recover data from such a system after one of its component storage devices (or its controller) crashes is pretty doubtful.

KISS principle - use the two SSD's as separate storage devices, get lots of speed from them, and get their full capacity.

 

[alceryes]

PLUS, you should realize if you use that system, there is no universal "standard" for that (just as there is no standard for RAID), so trying to recover data from such a system after one of its component storage devices (or its controller) crashes is pretty doubtful.

Windows 10 can span the disks (making them one big dynamic drive). When you get to the end of the first drive it just starts writing to the other. If you lose one disk you still have all the data on the other one.

 

[Paperdoc]

If you really want those two SSD's to operate as one, alceryes has a really good suggestion there, using a Windows utility to span the drives as a Dynamic Drive.