Is dual ssd Raid 0 worth it?

leandrodafontoura

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Yes for RAID 0, forget the above answer. There is almost no diference in risk compared to only 1 SSD, as you would have a backup running anyways, right? Moreover, since the SSDs would be exactly the same, they would both end up "failing" around the same time as if it was only one. And to conclude assuming you are on a 500GB ssd or more, that time would be more then 23 years.

And having 1 volume less to manage is always welcome
 


I don't want to get into an argument, but you're answer is not technically correct.

The failure rate of a RAID 0 setup is the x^(y*2), where x = failure rate of 1 drive and y= the number of drives... so a RAID 0 array featuring 2 hard drives with a 1.5% chance of failure in 1 year of use would have a failure rate of 1.5^(2*2) = 5% chance of failure in 1 year. A typical SSD with a GOOD uninterruptable power supply, a solid surge protector and an excellent PSU fails at about 1.25% in a year, which is roughly in line with the rate of failure of a normal hard drive. The problem with SSDs is, they're literally only as reliable as the power they get... So a power failure, or a bad power supply, or a power surge from bad power lines and no solid surge protector will pretty much corrupt a perfectly fine SSD. Now if you have a solid uninterruptable power system, a good surge protector and an excellent PSU, then sure, the risks of running a RAID 0 setup on your computer are no different then they are with a normal hard drive. If you lack those parts, then you'll see an astronomical increase in failure rate of your RAID setup.

Now setting the practicalities and statistics aside about the nature of a RAID 0 setup and the dependability of it, generally speaking a good SSD in a RAID 0 setup is too fast for the CPU to keep up. Even a top of the line intel will see almost no improvement in performance from a RAID 0 setup with SSDs, as the bottleneck once again shifts back to the CPU.

So with almost no appreciable improvement in performance and a much higher failure rate waiting for you, generally speaking a RAID 0 setup of SSDs is discouraged. Now there are some arguments that could be made about a RAID 10 or RAID 1 setup being beneficial... but RAID 10 is out of the conversation because the OP stated he was planning to use 2 SSDs, not 4... so as i said before in my prior post, if the OP wants a RAID 1 setup, sure he'll see some benefit.

 

mitch-ogb

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You should NEVER have any RISK or LOSS of data.

Backup Locally, Backup Offsite/ Backup Online.

You have insurance on your car, bike, house. Why not data? 1 year of Backblaze for unlimited data backup and versions is $50.
$50 of yearly insurance is INSANE for anything. Moreso your data.

Plan for the worst, always.
If you have a 10TB Backup raid system with redundancy at your house. that is great. What happens when your house burns down, someone steals it?
 

GregoryOrme

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An old thread, but since it was at the top of my Google search, maybe others are still visiting too.

There are three issues in the OP's question: data loss risk, financial investment, and performance.

As mitch-ogb notes, there are multiple ways to reduce the chance of data loss, and one should employ as many of these as practicable. I would expect drive failure at some point, regardless of the setup, but not the exponentially higher fail rates shown. For instance, www.raid-failure.com estimates (pessimistically, I might add) the 1-year and 5-year survival rates of one drive as 98 percent and 70 percent, respectively, and the survival rates for two drives in RAID 0 as 97 percent and 49 percent.

To me, if there were significant gains in performance and no great additional cost, then the setup would be worth it. If you are setting up software RAID, then the only additional immediate cost is for a second drive. However, because the two drives will work as one, this is not necessarily a great expense. If you were going to buy one 500~GB drive, you can now buy two 250~GB drives. Small drives often become cheaper per GB when larger drives are available.

So the real question of worth is in performance. Unfortunately, although you may get good benchmark scores on certain functions, that is no guarantee that you will actually experience any significant performance gains. Sometimes, setting up a faster hard drive or RAID merely exposes the weakness of an inexpensive or aging processor, shifting the bottleneck from slow HDDs to a slow processor. If your daily tasks are disk-intensive but rarely if ever max out the processor, then you could see some performance increase. However, if your processor is going full-tilt as you edit video or the like, then having a faster hard drive setup is not likely going to result in the perception of any performance improvement.

I have an older system and have maxed out the processor for the particular motherboard. I do not believe RAID 0 would make a difference in real-world performance. If you're like me and like to tinker with things, then it might be fun, but if you're doing it because you really have a need for speed, then I expect you may be disappointed.

 

faslane

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Aug 21, 2013
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Nope. The risk and cost benefits aren't worth it. Just buy two or one larger one and back it up to a 7200rpm spinner once in awhile. You won't gain squat for the money you spend and if it ever fails you lose two not one. (Depending on raid of course but there fast enough to not warrant messing with all the raid bs. When drives were slow it was worth it. With SSD. not at all. You'll barely if at all notice a speed increase whatsoever. Don't be fooled and told differently. It's a waste of time, money and what could be considered hassle.
 

ern2112

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Jul 26, 2016
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It is almost double the throughput of a single ssd and for me...thats substantial. How do I know? Ive tested it personally. I do video work and use the raid 0 for scratch. Failure? I have had a pair of raid ssd in raid 0 for 4 years running non stop...literally never turn off the machine...no issue at all. I also find it works well in usb3 too and have an evo 850 ssd for media and a pair of sandisk 256gb in raid 0 for scratch running on the macbook....so 3 drives working the data including the internal drive.

I come from the days we did this with scsi controllers and cuda 1gb drives. Even then, it was very reliable. Back up your data...and use the raid 0 as a scratch drive. Who cares if it goes down then? Its just cache. I do think that 2 is the maximum gain however...after that, it really isn't worth it. Good luck...hope you take the plunge. 250 bucks and you have a box and drives in raid 0....screams i tell ya....worth every penny.
 

Ribow81

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Jul 28, 2016
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OK my friend I read post below and become disapointed most of them think like dinosaurs and make you more confused so this is my experience and opinion.
1) raid 0 with ssd improves performance by 30-40% if made right and depends on system
2) If you are unlucky evrything can broke,HDD SSD even humans.By my experience with HDD is 10 years now not a single died I just replaced them as they become to old.I got SSD now for 2 years so experience is much less.
3) the critical point here is do you really need this improvement? to spend money on extra SSD? if so here my opinon-->
a) Save evry days important data/work on 3d disk or cloud.If you do so ---->
b) go for raid 0 with 2 SSD's since you need the improvement (in my opinion if its gaming/home desktop you dont need it)
c) if you do some kinda work with your pc like serious video editing etc and you need all your work need to be saved till last moment you were working you need Raid 10(that means 4 SSD's so more money)

ps: that simple it IS!!!!
 

ubermik

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I have just seen this and had some thoughts

Firstly, taking regular ghost images or similar makes any increased risk of data corruption a minor headache as the entire install includng all apps and updates to the point of the last imaging easy to copy back relatively quickly

A reasonably cheap way to improve OS speed would be to only get two of the fastest 120GB drives you can afford and put as little as possible on them, just the OS, apps and not much else, or just games that use the HDD a lot

You could also look at putting extra ram in the machine then use it as a drive cache for your games/apps drive. Or just get a third cheaper SSD in a larger size for those only paying for the top peformers on the two small raid drives this woud spread the data requests and transfers over more DMA channels and should give a slight improvement by itself as the OS isnt being held up as much by game loading

Alternatively as even with the absolute best theoretical gains which I believe arent really achievabe you could only get around 550mb/s x2 you could just splash the cash on a single full bore NVME X4 drive, the fastest of which hit benchmarks around 3000mb/s read and something like 2200mb/s write which is far in excess of anything sata three raid 0 could hope to achieve

Also bear in mind that driving (excuse the pun) an SSD hard (oh dear, another one), can lead to thermal throttling, so consider putting a high speed fan near the drive(s) to force cool air over them and help keep them cooler and thus reduce the chance of thermal throttling taking the speed back down to what you were getting with just one drive

Also if just one of the drives gets hot and throttles the raid set will run as slow as that one, so both need to be equally cooled to try and minimise or avoid throttling

I know its an old thread but as I just found it others will probably see it to, so it not a bad idea to still post on it even now for new people reading it.

 

TerrenceLeonard

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Oct 3, 2016
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I would expect that using RAID-0 with SSD, configured correctly, may increase your SSD lifespan. This is because SSD cells wear out as data is written to them. Striping balances the write load across disks; an array with 4 disks will spread 1/4 this work across each drive and so will increase the cells' longevity.

However, SSDs have wear-levelling algorithms (for example, NEVER defrag an SSD) to balance the wear load internally, and any RAID controller you use with SSD can work against this, wiping out any benefit. The trick is to get a decent RAID card and firmware that supports SSD.

Finally, you will see a performance increase but for the vast majority of people this is academic; as rightfully said here by others, all you do is move the bottleneck. I would use this for wear leveling but not performance. The trade-off is, if one disk fails you lose all the data, so you should always have a decent backup in place anyway.