Personal computing discussed
Moderators: renee, morphine, Steel
moriz wrote:i've been running a RAID0 intel 320 120GB for months now. ran into problems with one of the SATA cables of all things, but the array itself remained fine. the lack of TRIM hasn't been an issue so far.
moriz wrote:i've been running a RAID0 intel 320 120GB for months now. ran into problems with one of the SATA cables of all things, but the array itself remained fine. the lack of TRIM hasn't been an issue so far.
paulsz28 wrote:Hmm, a 1TB, quad-SSD RAID-0 Photoshop box sounds interesting! I can see how continual Photoshop image processing/transferring could benefit from quick storage solutions. RAID is good for FREQUENT storage accesses, but not good for infrequent level loads and web browsing (my opinion). I recently looked at RAID-ing two SSDs, and decided my typical computer usage would not warrant the extra cost/complexity of RAID, so I went with a single Corsair Force GT 120GB, and it's PLENTY fast for the things I do (Outlook, Excel, Word, web browsing, games a few times a week, etc.). Again, Photoshop is probably in the category of applications that would benefit significantly from an SSD due to how much data is being passed.
Is the quad setup truly necessary, or can you get by with just two drives? Have you used just a single SSD for your purposes yet (if not, you might be surprised at wicked performance)? Those are more rhetorical questions than requiring forum feedback.
One thing I found out about RAIDing SSDs during my research about a month ago is that say you need to update the firmware on your SSDs, well you have to break the array to update each drive individually (someone correct me if I'm wrong). This would required ANOTHER drive sitting around with an OS ready to process firmware updates. Although, with the latest Corsair firmware I'm using, I've had not one problems at all. So firmware updates may not be required with drives running more recent firmware - the issue might not even come up.
Not trying to make you doubt your approach, just sharing. Hope it goes well for. Let us know about Photoshop time/performance improvements for the image processing.
JdL wrote:moriz wrote:i've been running a RAID0 intel 320 120GB for months now. ran into problems with one of the SATA cables of all things, but the array itself remained fine. the lack of TRIM hasn't been an issue so far.
Nice. Have you noticed any difference in performance compared to non-RAID SSD?
moriz wrote:also on a related note, if you want to go ahead with this, make frequent backups. i use acronis 2011 to make daily incremental backups.
cynan wrote:I think the pertinent points have already been covered, but the issues with SSDs in RAID 0 are:
1)Lack of TRIM support. Don't really know if this is an issue. But if it is, it will likely crop up after you have had the array for a couple of years or longer.
2)Minimal performance benefit over a single larger SSD. The SATA controller and/or the OS or programs normally used just can't make use of the extra bandwidth. Additionally, larger SSDs generally have faster read speeds, negating the increase in read speed performance that is the whole point of RAID 0 (In other words, often a 512GB SSD can be thought of as a RAID 0 version of two 256GB SSDs).
3)Traditional problems in the event of physical disk or RAID array failure with RAID 0.
Compton wrote:Basically, no striped RAID configuration's small randoms are going to scale since they're below the stripe size. So if you're dragging copying large sequentials to the drive you could do so very quickly.
TheWacoKid wrote:Compton wrote:Basically, no striped RAID configuration's small randoms are going to scale since they're below the stripe size. So if you're dragging copying large sequentials to the drive you could do so very quickly.
Except that small random reads below the stripe size can still be twice as fast since there are two drives servicing requests rather than one...
moriz wrote:for RAID0 to have any benefit, the stripe size needs to be smaller than the size of the data. for intel's matrix RAID, the smallest stripe size is 4K, which means that it doesn't do anything for 4K transfers. for anything bigger, there's a theoretical double in performance with two identical drives, which i find to be generally true. my RAID0 intel 320 120GB can achieve 460/220 sequentials, which is pretty close to double the expected speed of each drive.
Compton wrote:moriz wrote:for RAID0 to have any benefit, the stripe size needs to be smaller than the size of the data. for intel's matrix RAID, the smallest stripe size is 4K, which means that it doesn't do anything for 4K transfers. for anything bigger, there's a theoretical double in performance with two identical drives, which i find to be generally true. my RAID0 intel 320 120GB can achieve 460/220 sequentials, which is pretty close to double the expected speed of each drive.
Yes, and anything below the stripe size gets handled off of one drive. My Intel's or Indilinxes in RAID 0 are pretty good, and files above the stripe size just about get doubled. But that doesn't make two drives "twice as fast" in terms of real performance.
Two Intel X25-M 80GB drives in RAID 0 have max sequentials in the 520/160 read/write neighborhood. And add in the 4K randoms for one drive 24/60 MBs read/write.
That makes two X25-M 80s equivalent in speed to one 6gbps Samsung 830 64GB drive (520 read 160 writes, 20/60 4K randoms), at least in numbers. Striping SSDs is cool, but saying that you have two drives to fulfill sub-stripe size requests is just not true. You'll get a boost in speed, but it won't be in small files/small random performance, and you won't feel like your storage system is twice as fast. That said, it's still awesome, but be realistic about the results.
Two Patriot WildFire/Mushkin Chronos Deluxe 120s in RAID would top out at 1000MBs reads and 500MBs writes (with incompressible data). Small randoms for one drive are pretty good, and the speed is impressive. But it's not like Windows is going to start twice as fast or Skyrim load levels twice as fast.
moriz wrote:intel claims that their next RST driver will enable TRIM for RAIDed SSDs, so that should solve a lot of problems. however, OP's system is an AMD, most of them don't have Intel's Matrix RAID, not to mention access to intel RST drivers. with that said, most modern drives have good enough garbage collection that TRIM isn't needed that much. the intel 320 series happens to have very good GC, so most of them time, it doesn't particularly need TRIM anyway.
also, larger SSDs often don't have faster read speed, but do have faster write. in every case though, 2x120GB will end up being almost twice as fast as 1x240. for instance, 2x crucial m4 128GB can hit 1GB/s sequential read.
kamikaziechameleon wrote:So as I'm changing jobs and some investments are maturing I'd like to finally start laying the groundwork for this to happen. What would I need for Trim to function in RAID0??? What SSDs would you all recommend for such a venture? I'm looking to do a 1 or 2 gb array and then back it up on a 2 gb caviar green drive. I'd be doing this in about 3 months or 4 months time. Thanks for all the info up to this point.
just brew it! wrote:I don't see the point. Real-world performance isn't going to be noticably better in most cases, the total cost is going to be about the same as a single larger SSD, you've got the (potential) TRIM issue, and the odds of data loss are much higher. Why bother?
Compton wrote:TheWacoKid wrote:Except that small random reads below the stripe size can still be twice as fast since there are two drives servicing requests rather than one...
I really don't think that's true, but even if it is, how would two drives service one 4K file that's only on one drive? Or if the 4K file was on both drives, how does it read from both any faster than one?
cynan wrote:How else can you get 900 Mb/s sequential read speeds on benchmarks for a relatively low investment (ie, no PCIe SSDs)?
Waco wrote:
The hassle for RAID 0 just isn't worth it for the benefits you get. A single larger drive will always be my recommendation.
kamikaziechameleon wrote:moriz wrote:intel claims that their next RST driver will enable TRIM for RAIDed SSDs, so that should solve a lot of problems. however, OP's system is an AMD, most of them don't have Intel's Matrix RAID, not to mention access to intel RST drivers. with that said, most modern drives have good enough garbage collection that TRIM isn't needed that much. the intel 320 series happens to have very good GC, so most of them time, it doesn't particularly need TRIM anyway.
also, larger SSDs often don't have faster read speed, but do have faster write. in every case though, 2x120GB will end up being almost twice as fast as 1x240. for instance, 2x crucial m4 128GB can hit 1GB/s sequential read.
So as I'm changing jobs and some investments are maturing I'd like to finally start laying the groundwork for this to happen. What would I need for Trim to function in RAID0??? What SSDs would you all recommend for such a venture? I'm looking to do a 1 or 2 gb array and then back it up on a 2 gb caviar green drive. I'd be doing this in about 3 months or 4 months time. Thanks for all the info up to this point.
just brew it! wrote:I don't see the point. Real-world performance isn't going to be noticably better in most cases, the total cost is going to be about the same as a single larger SSD, you've got the (potential) TRIM issue, and the odds of data loss are much higher. Why bother?