Samsung 950 Pro 256GB RAID Report
When it comes to flash capacity, more is better. The question is whether two are better than one. Today, we look at the Samsung 950 Pro 256GB SSD again, but with a focus on pairing two drives in a RAID 0 array. This option costs a little more than a single Samsung 950 Pro 512GB, but does the array offer a performance advantage that makes up the price difference?
Non-volatile Memory Express (NVMe) is a new storage protocol designed to reduce latency in the software stack for flash and next-generation solid-state media. There are only two viable client-flash processors available in the M.2 form-factor: the Samsung UBX and the Toshiba TC58NCP0706SB (found in the Toshiba XG3 and the upcoming OCZ Storage Solution's RevoDrive 400).
The Samsung UBX flash processor has been on the market for nearly a year now. It first appeared in the SM951-AHCI and later came to market with NVMe in the SM951-NVMe and PM953, both OEM products sold to system builders. Samsung eventually brought the UBX controller to the retail market in the 950 Pro, and it is one of the best-performing SSDs available today.
Samsung released the 950 Pro in only two capacity sizes—256GB and 512GB. The company claimed a 1TB model would follow the initial release in early 2016 but that drive has yet to appear. In our first review of the 950 Pro, we tested three configurations with a single 256GB, a single 512GB and two 512GB drives in a RAID 0 array. We didn't have access to a second 950 Pro 256GB drive to obtain RAID numbers during the test, but that changed last week when Samsung shipped us a full retail 256GB drive to round out our coverage.
Specifications
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Samsung 950 Pro 256GB
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- Form Factor
- Single-Sided M.2 2280
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- Controller
- Samsung UBX 3-Core
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- DRAM
- Samsung LPDDR3 512 MB
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- Flash
- Samsung 32-Layer MLC V-NAND
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- Custom NVMe Driver
- ✓
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- Sequential Read
- 2,200 MB/s
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- Sequential Write
- 900 MB/s
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- Random Read
- 270,000 IOPS
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- Random Read QD1
- 11,000 IOPS
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- Random Write
- 85,000 IOPS
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- Random Write QD1
- 43,000 IOPS
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- Active Maximum Power
- 6.4 W
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- Idle Power
- 70 mW
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- DEVSLP
- 2.5 mW
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- Endurance
- 200 TBW
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- Warranty
- 5 Years
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Samsung 950 Pro 512GB
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- Form Factor
- Single-Sided M.2 2280
-
- Controller
- Samsung UBX 3-Core
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- DRAM
- Samsung LPDDR3 512 MB
-
- Flash
- Samsung 32-Layer MLC V-NAND
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- Custom NVMe Driver
- ✓
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- Sequential Read
- 2,500 MB/s
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- Sequential Write
- 1,500 MB/s
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- Random Read
- 300,000 IOPS
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- Random Read QD1
- 12,000 IOPS
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- Random Write
- 110,000 IOPS
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- Random Write QD1
- 43,000 IOPS
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- Active Maximum Power
- 7 W
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- Idle Power
- 70 mW
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- DEVSLP
- 2.5 mW
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- Endurance
- 400 TBW
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- Warranty
- 5 Years
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The 950 Pro 256GB compares well to the larger 512GB model, but there are some key differences in performance and endurance. That starts with the 300 MB/s sequential read difference that favors the larger drive. The 950 Pro 256GB takes an even larger cut with sequential write speed, a 600 MB/s loss. The 256GB model also has half the endurance, but that's to be expected given the low number of NAND die Samsung needs to reach these capacities.
Random performance is also slightly different. The same can be said about the power consumption.
The 950 Pro uses Samsung's UBX PCIe 3.0 x4 to flash controller. The UBX was configured to support the NVMe protocol, which reduces latency and allows random performance to increase due to greater parallelism. The NVMe-enabled controller is paired with Samsung's 32-layer V-NAND and a single 512MB DRAM buffer used to cache map data.
Pricing, Warranty And Accessories
The 950 Pro 256GB currently sells for as low as $190, while the 512 GB sells for $330. Two 950 Pro 256GB drives cost about $50 more than the single, larger-capacity drive. Today we'll see if the performance of two drives makes up the difference.
The 950 Pro products ship as bare drives but Samsung allows users to download two useful software packages. The first is Magician, an SSD toolbox that allows users to monitor the status of Samsung SSDs, optimize operating system conditions, and perform some disk-management operations. Samsung also has a custom data-migration tool that allows users to clone data from an existing drive and transfer to your new Samsung drive.
A Closer Look
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Prod_002
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Prod_003
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Prod_004
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Prod_005
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Prod_006
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Prod_007
Not much has changed with the 950 Pro since we first tested them other than the final sticker on the drive itself. For comparison, there is an image of the NDA-release sample and the final retail sample together.
A lot of people do.
Assuming that the performance gains we saw with spinning disks in RAID 0 automagically does the same with SSD's. It does not.
Someone just explained 24 months of my life:)
that's the point of faster drives, loading it all in ram. do you think it magically appears there by itself ?
iirc i was told samsung driver is better than MS but that might change when MS updates. tbh i dont believe in samsung's software too much.
overall great article, it is very sad to see going to raid 0 loses performance in most important area, 4k read/4k write takes huge hit and almost no point going into that exception is sequential read. it maybe good for games or video editing, where as everything else its better to go for 1 drive, kinda sad.
maybe when optane comes out we'll see this problem solved as driver has more time to mature?
All that does is load levels faster. It doesn't translate to faster in-game framerates. A few world streaming games won't see the stutter when you open a door in a building. But your post could confuse others. A SSD doesn't necessarily "load it all in RAM." That's up to your RAM capacity and the game engine of how many resources get sent to RAM.
But RAID 0 is really n-drive performance increase. Why didn't you test with 3 drives as the motherboard supports it?
exactly, a faster cpu and a very well coded game to take advantage of newer instruction would greatly help for sure. SSD right now with raid 0 almost doubles the sequential throughput but theres very little advantage to it in using windows. gaming, video editing thats about it, and sequential file copying? unsure about image back up/restoring.
although OS it self has a lot of files that reads sequential most are random performance, in a case of NVMe PCIE raid 0 it's almost pointless because QD1 to QD2 performance actually drops in comparison to two drives.. like wtf samsung?
there are aritcles out there tested raid 0 with 3 SSD on another website i think pcper? but still the same, sequential goes way up, random performance drop, kinda sad.
We don't show HDDs because the results are very different. If you want I can make a post with all of the benchmarks in the forums in a few days. I have the data, I just need to build the charts. Give me a couple of days and I'll whip the charts up.
We only had two identical drives at the time. We now have three drives. I have a review coming with three drives in RAID 5.
This would actually be great, Chris. I don't think you need a huge comprehensive list, just a simple one that shows the reviewed drive against a couple of the more popular current SSDs and some common 7200 and 5400 3.5" drives ( a WD Black, Blue, and Green should be good ). That'd give a good idea of the relative real-world performance gain.
On a slightly unrelated tangent, I would love to see a new HDD review. I think it'd be great to see how much spindle drives have improved in the last few years. I mean with platter density and other improvements, can current 5400 drives match or outperform older 7200 drives?
I did that with 3 74 GB Raptors in Battlefield 2 before I could afford an SSD big enough.