2 ssd's on raid 0, is it possible?

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AndreRio

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how crazy is it to have 2 ssd's on raid 0, is it a crazy thing to do or is it ok?
 
It's not that crazy, especially if your SSDs are small. I personally have 3x60GB SSDs in RAID0. Mine are older models that don't support TRIM so I don't care as much about TRIM support in RAID0.
 
Next question I would ask is: "Is it worth it?"
Personally I'd choose more ssd space over an even faster ssd setup unless you have particular large files you move around all day.
 
AndreRio said:
how crazy is it to have 2 ssd's on raid 0, is it a crazy thing to do or is it ok?
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This will be fine if you like benchmarks or do a lot of reading and writing GB files sequentially but it will not in general help real world application performance. It could actually hurt your every day performance (increase latency lower IOPS) since most raid controllers are not designed for SSDs. Although if you spend $400+ and get one of the SAS raid controllers that are designed for SSDs (LSI 926X + Fastpath) you will certainly not sacrifice application performance to obtain higher large file sequential reads and writes.
 
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Thanks all. I was thinking on buying 2 crucial m4 512gb ssds, and run them in raid0. What I wanted to know is, do ssds in raid function/last long enough? I heard that ssds don't last in raid??
 
What I wanted to know is, do ssds in raid function/last long enough? I heard that ssds don't last in raid??
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I would not worry about that for such large SSDs since they have way more cells to wear level. I would expect these to last several times as long as a 1TB hard drive.
 
It is possible, but IMO a pain that's not worth it. SSD's are so fast anyways that you won't see a huge performance increase. Instead you get the higher possibility of data corruption, and normally a higher cost.
 
I would not recommend RAID for most users, but if you are willing to buy 1TB of flash, then yeah I'd say go for it. Don't forget to buy an HDD to back it up regularly and you're set.
 
Running 2x M4 256GB in RAID0 on a heavily used system, absolutely no problems and it's mind numbingly fast.

Run 2x Vertex 3's on a similar system with similar results.

Ran 3x Intel G2 80GB drives on a P45 board, again with fantastic results.

I'm not sure where the 'it's too much of a pain' applies as mentioned in a previous post - setup is no different than RAIDing mechanical drives. Some people.... sheesh.



The big caveat with SSDs and RAID arrays comes from the lack of TRIM support. Without TRIM and on SSDs without advanced garbage collection algorithms, WRITE performance can degrade as the drive has to do more read-erase-write and relocate operations over time. This effect (and write amplification in general) can get really bad if you keep SSDs (in the array) at or near full to capacity. Over a protracted period of time WRITE performance of the SSDs (in the array) WILL decrease...

This effect isn't permanent to the SSDs and if, over time, the performance decrease becomes too much you can start from scratch - that is, drop the array and perform an ATA 'SECURITY_ERASE' command on each of the SSDs. The ATA secure erase command erases every block on the SSD and basically returns it to the performance it had when it was new. (Alternatively you could just reformat the SSD and put it in a TRIM environment and over a short period of time performance would return to normal)

My own personal experiences with SSDs in RAID0 have been nothing but positive. I think that as an enthusiast who likes to eek out every drop of performance in my hardware, the benefit is tangable and well worth it. If eventually I actually need to perform a secure erase, then that's no problem. I do it every time I sell a drive anyway whether it's an SSD or mechanical drive. *shrug*


Now, as for TRIM support in RAID arrays? Honestly no one but Intel has a clue. Intel began promising support last year in driver release notes, and recently there have been unconfirmed reports on the enthusiast communities of TRIM-in-RAID working with obscure Intel OROM, beta RST driver, and hardware combinations. There are even rumors floating around that because of the way Windows 7 recognizes Intel's RAID hardware (as an SCSI device), TRIM-in-RAID will NEVER work on Windows 7 and therefore it will only work in Windows 8 with it's new driver implementation. This whole issue is complicated further by the fact that, short of extensive low level examination of SSDs in use, there is no way to actually TELL that TRIM-in-RAID is working. It's a FUSTERCLUCK.
 
I'm new to the SSD world, but after reading a bit I found out some interesting info.

If you are interested in the fastest possible SSD and you have mad cash available, would it be a good idea to consider a PCIe type SSD?

Here are a few links that talk about the ridiculous speed of these type of cards...

http://www.geek.com/articles/chips/...00gb-pcie-ssd-with-2gbs-read-speeds-20120412/

http://www.engadget.com/2012/01/06/ocz-details-forthcoming-z-drive-r5-enterprise-ssd-claims-its-t/

Not cheap by any means, but the intel article mentions that before too long we may see this type of performance at more reasonable costs. It would be nice to have these options, unless there are any drawbacks to these type of cards that I'm not aware of.
 
Ya, expensive and they take up PCI-E slot(s) that may be needed for gpu's etc.
 
You won't gain anything in access speeds and your 4K speeds are already incredibly fast on a current SSD. So as far as just standard desktop browsing and small files you aren't going to notice the difference. Large file transfers you'll notice the speed, but you'll be limited by the speed of the other device (unless transferring to/from memory).

benchmarks will be great, but I think after you reach a couple hundred megabytes per second transfer speeds you start to not notice the difference. And the access times are really the coup de grâce of SSD's and RAID 0 won't improve that on any device.
 
anyone suggesting a pci-e ssd instead of raid0 is ignoring that pci-e ssds are nothing more than raid0s done for you

they're good, but the raiding of your own ssds allows for much more flexibility
 
Vega said:
Ya, expensive and they take up PCI-E slot(s) that may be needed for gpu's etc.
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Lol, not everybody has 4 graphics cards :p

But yes, that can be a problem depending on motherboard/rig.
Some people never plan to use sli/crossfire though so it is a perfectly viable option.
 
gjs278 said:
anyone suggesting a pci-e ssd instead of raid0 is ignoring that pci-e ssds are nothing more than raid0s done for you

they're good, but the raiding of your own ssds allows for much more flexibility
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Not necessarily. The main advantage of a PCI-E based SSD is that they support TRIM.

Also, I don't know how other PCI-E ssd drives work, but certain revisions of the OCZ RevoDrive X2 allow you to choose if you want RAID 1 or RAID 0 or JBOD.

Additionally, the Revodrive 3 X2 (X2 = 2 ssd's on the PCI-e board) has read speeds at ~1400mb/s which two SSDs in RAID 0 can't touch (though most consumers won't have a need to utilize such speeds).
A 240GB Revodrive 3 X2 is about $430.

The regular 240GB Revodrive 3 (single ssd on PCI-e board) goes for $300 and reads at about 900mb/s which is about the same as two regular SSDs in RAID 0--plus you get TRIM.

PCI-Express SSDs now seem like a viable option.

The big negatives with the Revodrives, in my experience, is that they add heat to your system (whereas SSDs virtually add none) so OC'd systems may not take to them well. The Revodrive X2's specifically give off significant heat.

And, of course, taking up a PCI-Express slot itself is generally viewed as a negative, though I personally never use all of my PCI-Express slots.

Getting Windows to install the OS on a RevoDrive can be tricky. It took me a couple hours to get the Windows Setup environment to load the drivers correctly.

If you're willing to spend the cash on two SSDs in RAID 0, then PCI-e SSD drives are worth considering.
 
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nellie7979 said:
Not necessarily. The main advantage of a PCI-E based SSD is that they support TRIM.
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not all of them, and as it turns out, not too relevant for many raid arrays. take a look at the following chart:

http://www.tweaktown.com/reviews/42...rive_3_x2_pci_e_480gb_ssd_review/index10.html

as we can see here, the write performance of a revodrive drops very quickly at the 25% full mark. it maintains that performance level for basically every other percentage full, so having a revodrive at 75% full is going to perform as well as one 25% full according to this.

this means that the only advantage given to you by trim is if you are looking to increase write performance while your 480gb revodrive is BELOW 25% full. if you have trim, the only portion of that chart that would restore itself would be the last green line, it would shoot back to the 80k level when empty.

now on that same chart, scroll to the m4. the m4, without trim, is able to restore itself to a full performance level with garbage collection alone when empty and idle. the corsair performance 3 even farther down doesn't care what you fill it with, it has a stable write experience and would gain nothing big from having trim.

now let's head over to this chart about the plextor m3p

http://www.tweaktown.com/reviews/46..._128m3p_solid_state_drive_review/index10.html

as we can see here, without trim, the 128gb plextor m3p is able to outperform a 480gb revodrive 3 in every single performance level for data in use testing. it even has garbage collection to restore the drive performance to full, leaving zero use for trim on this drive either when given time to idle.

nellie7979 said:
Also, I don't know how other PCI-E ssd drives work, but certain revisions of the OCZ RevoDrive X2 allow you to choose if you want RAID 1 or RAID 0 or JBOD.
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yes, but you can also do that and more with your own raid solution.

nellie7979 said:
Additionally, the Revodrive 3 X2 (X2 = 2 ssd's on the PCI-e board) has read speeds at ~1400mb/s which two SSDs in RAID 0 can't touch (though most consumers won't have a need to utilize such speeds).
A 240GB Revodrive 3 X2 is about $430.
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1,400mb/s when working with all zeroes. when working with uncompressed data, it drops to the low rate of 690mb/s

http://www.tweaktown.com/reviews/42...drive_3_x2_pci_e_480gb_ssd_review/index6.html

you can touch that level of performance with two plextor m3ps.

nellie7979 said:
The regular 240GB Revodrive 3 (single ssd on PCI-e board) goes for $300 and reads at about 900mb/s which is about the same as two regular SSDs in RAID 0--plus you get TRIM.
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again, that is when working with all zeroes.

nellie7979 said:
PCI-Express SSDs now seem like a viable option.

The big negatives with the Revodrives, in my experience, is that they add heat to your system (whereas SSDs virtually add none) so OC'd systems may not take to them well. The Revodrive X2's specifically give off significant heat.

And, of course, taking up a PCI-Express slot itself is generally viewed as a negative, though I personally never use all of my PCI-Express slots.

Getting Windows to install the OS on a RevoDrive can be tricky. It took me a couple hours to get the Windows Setup environment to load the drivers correctly.

If you're willing to spend the cash on two SSDs in RAID 0, then PCI-e SSD drives are worth considering.
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maybe if you don't have native 6gb/s intel ports. otherwise you can raid two plextor m3ps and basically outperform a revodrive when working with random data. if you're willing to go for an actual raid card as well, you can really leave a revodrive in a sad state.
 
The PCI slot based drives do free up the standard SATA ports though if you need them for several optical disks as well as adding a software RAID.
 
On Newegg at the moment, I see no price benefit to doing two smaller drives instead of a larger one, at least for the Crucial M4 line. I am lazy and did not look at other brands.

Crucial M4 32GB $55
Crucial M4 64GB $75
Crucial M4 128GB $100-$110
Crucial M4 256GB $210
Crucial M4 512GB $400

Would performance of two smaller SSDs in RAID be meaningfully better than a single large one? Does the lack of working TRIM in RAID make them perform worse?

Does RAID 0 still has the consideration that if one drive fails, you lose all data irrecoverably, having to go back to your backup?

Unless you have a seriously good reason to have more than 512GB in one volume, I'm seeing a lot more problems than benefits.
 
Does RAID 0 still has the consideration that if one drive fails, you lose all data irrecoverably, having to go back to your backup?
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Yes. Although there is some chance of recovering data from the working drive. Any files that were smaller than the chunk size that are entirely on the good disk would be recoverable provided you can find them.

Would performance of two smaller SSDs in RAID be meaningfully better than a single large one?
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Sequential transfer rate will most likely be better in raid 0. You can get nearly 100% improvement in STR for a 2 drive raid0. However in most cases that will not help application performance because most applications do not read or write large files sequentially.
 
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JayJapanB said:
Next question I would ask is: "Is it worth it?"
Personally I'd choose more ssd space over an even faster ssd setup unless you have particular large files you move around all day.
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Games that require steaming data like World of Warcraft seem to benefit the most. Back in the good ol hard drive days it took a few seconds for a guy to show in my screen when the guy on vent was telling me he's right next to me with my wonderful 40ms. Now with a SSD there is virtually any loading from what I've seen. I just wish it would use all of my system memory if it could. Hurry up 64-bit games!
 
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