It has become increasingly apparent that flash memory die shrinks have hit a bit of a brick wall in recent years. The issues faced by the standard 2D Planar NAND process were apparent very early on. This was no real secret - here's a slide seen at the 2009 Flash Memory Summit:
Despite this, most flash manufacturers pushed the envelope as far as they could within the limits of 2D process technology, balancing shrinks with reliability and performance. One of the largest flash manufacturers was Intel, having joined forces with Micron in a joint venture dubbed IMFT (Intel Micron Flash Technologies). Intel remained in lock-step with Micron all the way up to 20nm, but chose to hold back at the 16nm step, presumably in order to shift full focus towards alternative flash technologies. This was essentially confirmed late last week, with Intel's announcement of a shift to 3D NAND production.
Intel's press briefing seemed to focus more on cost efficiency than performance, and after reviewing the very few specs they released about this new flash, I believe we can do some theorizing as to the potential performance of this new flash memory. From the above illustration, you can see that Intel has chosen to go with the same sort of 3D technology used by Samsung - a 32 layer vertical stack of flash cells. This requires the use of an older / larger process technology, as it is too difficult to etch these holes at a 2x nm size. What keeps the die size reasonable is the fact that you get a 32x increase in bit density. Going off of a rough approximation from the above photo, imagine that 50nm die (8 Gbit), but with 32 vertical NAND layers. That would yield a 256 Gbit (32 GB) die within roughly the same footprint.
Representation of Samsung's 3D VNAND in 128Gbit and 86 Gbit variants.
20nm planar (2D) = yellow square, 16nm planar (2D) = blue square.
Image republished with permission from Schiltron Corporation.
It's likely a safe bet that IMFT flash will be going for a cost/GB far cheaper than the competing Samsung VNAND, and going with a relatively large 256 Gbit (vs. VNAND's 86 Gbit) per-die capacity is a smart move there, but let's not forget that there is a catch - write speed. Most NAND is very fast on reads, but limited on writes. Shifting from 2D to 3D NAND netted Samsung a 2x speed boost per die, and another effective 1.5x speed boost due to their choice to reduce per-die capacity from 128 Gbit to 86 Gbit. This effective speed boost came from the fact that a given VNAND SSD has 50% more dies to reach the same capacity as an SSD using 128 Gbit dies.
Now let's examine how Intel's choice of a 256 Gbit die impacts performance:
- Intel SSD 730 240GB = 16x128 Gbit 20nm dies
- 270 MB/sec writes and ~17 MB/sec/die
- Crucial MX100 128GB = 8x128Gbit 16nm dies
- 150 MB/sec writes and ~19 MB/sec/die
- Samsung 850 Pro 128GB = 12x86Gbit VNAND dies
- 470MB/sec writes and ~40 MB/sec/die
If we do some extrapolation based on the assumption that IMFT's move to 3D will net the same ~2x write speed improvement seen by Samsung, combined with their die capacity choice of 256Gbit, we get this:
- Future IMFT 128GB SSD = 4x256Gbit 3D dies
- 40 MB/sec/die x 4 dies = 160MB/sec
Even rounding up to 40 MB/sec/die, we can see that also doubling the die capacity effectively negates the performance improvement. While the IMFT flash equipped SSD will very likely be a lower cost product, it will (theoretically) see the same write speed limits seen in today's SSDs equipped with IMFT planar NAND. Now let's go one layer deeper on theoretical products and assume that Intel took the 18-channel NVMe controller from their P3700 Series and adopted it to a consumer PCIe SSD using this new 3D NAND. The larger die size limits the minimum capacity you can attain and still fully utilize their 18 channel controller, so with one die per channel, you end up with this product:
- Theoretical 18 channel IMFT PCIE 3D NAND SSD = 18x256Gbit 3D dies
- 40 MB/sec/die x 18 dies = 720 MB/sec
- 18x32GB (die capacity) = 576GB total capacity
Overprovisioning decisions aside, the above would be the lowest capacity product that could fully utilize the Intel PCIe controller. While the write performance is on the low side by PCIe SSD standards, the cost of such a product could easily be in the $0.50/GB range, or even less.
In summary, while we don't have any solid performance data, it appears that Intel's new 3D NAND is not likely to lead to a performance breakthrough in SSD speeds, but their choice on a more cost-effective per-die capacity for their new 3D NAND is likely to give them significant margins and the wiggle room to offer SSDs at a far lower cost/GB than we've seen in recent years. This may be the step that was needed to push SSD costs into a range that can truly compete with HDD technology.
Subject: Storage | November 24, 2014 - 04:35 PM | Jeremy Hellstrom
Tagged: ssd, sata, PS3110-S10, phison, Neutron XT, corsair, 256GB
Allyn recently reviewed the Corsair Neutron Series XT but as it is a brand new controller it is always worth a second opinion. The Tech Report also recently tested this SSD, with its four core PS3110 controller and A19 variant of Toshiba's 19-nm MLC NAND. Three of those cores are devoted to behind the scenes tasks such as garbage collection which should help performance when the drive starts to approach full capacity. When testing performance they did see improvements from the first Phison controlled drive, the Force Series LS which sits at the bottom of their performance ranking. That was not all that held back this drive, lack of support for features which have become common such as Microsoft eDrive put this drive behind the top competition and if Corsair is to make this drive a contender they are going to have to think very carefully about what the MSRP will be.
"Corsair's new Neutron Series XT pairs a quad-core Phison controller with Toshiba's latest MLC NAND. We've taken the 240GB version for a spin to see if it can hang with the big boys."
Here are some more Storage reviews from around the web:
- Corsair Neutron XT (240GB) @ The SSD Review
- ADATA SP610 512GB SSD @ Kitguru
- Synology Diskstation DS115J 1-Bay NAS @ eTeknix
- QNAP TurboNAS TS-653 Pro NAS Server Review @ NikKTech
- Western Digital My Passport Pro 2 TB Portable (Thunderbolt) @ TechARP
- OWC Thunderbay 4 mini Thunderbolt 2 Enclosure @ The SSD Review
Introduction, Specifications and Packaging
In recent years, Plextor has branched beyond their renowned lines of optical storage devices, and into the realm of SSDs. They have done fairly well so far, treading carefully on their selection of controllers and form factors. Their most recent offerings include the M6S and M6M (reviewed here), and are based on Marvell controllers coupled with Toshiba flash. Given that the most recent Marvell controllers are also available in a PCIe variant, Plextor also chose to offer their M6 series in PCIe half height and M.2 form factor. These last two offerings are not simply SATA SSDs bridged over to PCIe, they are natively PCIe 2.0 x2 (1 GB/s), which gives a nice boost over the current SATA limit of 6Gb/sec (600 MB/sec). Today we are going to kill two birds with one stone by evaluating the half-height PCIe version:
As you can see, this is nothing more than the M.2 version on a Plextor branded interposer board. All results of this review should be identical to the bare M.2 unit plugged into a PCIe 2.0 x2 capable M.2 port on either a motherboard or mobile device. Note that those devices need to support the 2280 form factor, which is 80mm in length.
Here's the M.2 version installed on an ASUS X99-Deluxe, as tested by Morry.
Introduction, Specifications and Packaging
At that time we only knew that Phison was going to team up with another SSD manufacturer to get these to market. We now know that manufacturer is Corsair, and their new product is to be called the Neutron XT. How do we know this? Well, we've got one sitting right here:
While the Neutron has not officially launched (pricing is not even available), we have been afforded an early look into the performance of this new controller / SSD. While this is suspected to be a cost effective entry into the SSD marketplace, for now all we can do is evaluate the performance, so let's get to it!
Meet the Inateck barebones tool-free HDD
Recently Inatek sent over two products to test out, the FEU3NS-1 USB 3.0 HDD Tool Free External Enclosure and the BP2001 10W Bluetooth Stereo Speaker. Inatek has been around for a while, though originally their products were only available in the EU they have recently expanded to North America. They sell a variety of peripherals such as PCIe USB cards, cables and chargers as well as Bluetooth input devices and mobile device protectors, in addion to external HDDs enclosures and of course Bluetooth speakers.
The first product to take a look at is the USB 3.0 enclosure which ships with a USB cable and manual in addition to the tool free USB HDD enclosure. It is a very simple product at a very low price and is small enough to stick in a laptop bag without having an unsightly bulge. The base model is currently $14 on Amazon and for an extra $5 you can get one which supports USB Attached SCSI Protocol to allow an SSD to hit full speed when installed in the enclosure. The USB 3.0 cable is a dual male cable; no proprietary plugs or breakable adapters needed to make this work and as enough power can be provided over USB that this is the only cable you will need. The only compatibility issue concerns the relatively uncommon 12mm 2.5" drives which will not fit, 9.5mm and 7mm are both acceptable and there is a removable cushion to keep your 7mm drive nice and snug.
Subject: Storage | November 14, 2014 - 02:00 PM | Jeremy Hellstrom
Tagged: btrfs, EXT4, XFS, F2FS, 530 series, Intel, raid, unix humour, linux
When you use Linux you have a choice as to which file system you wish to use, a choice that never occurs to most Windows users but can spark an argument every bit as vicious as the eternal debate over EMACS versus VIM versus whichever text editor you prefer. There has not been much SSD benchmarking done on alternate files systems until now, Phoronix has benchmarked the Intel 530 series SSD in numerous configurations on Btrfs, EXT4, XFS, and F2FS. With four of the 120GB model available they were able to test the speed of the drives in RAID 0, 1, 5, 6, and 1+0. There is obviously still some compatibility issues as some tests failed to run in certain configurations but overall these drives performed as expected. While the results did not vary widely it is worth reading through their article if you plan on building a high speed storage machine which will run Linux.
"Following the recent Btrfs RAID: Native vs. Mdadm comparison, the dual-HDD Btrfs RAID benchmarks, and four-SSD RAID 0/1/5/6/10 Btrfs benchmarks are RAID Linux benchmarks on these four Intel SATA 3.0 solid state drives using other file-systems -- including EXT4, XFS, and Btrfs with Linux 3.18."
Here are some more Storage reviews from around the web:
- Samsung XS1715 (1.6TB) @ The SSD Review
- Angelbird SSD2go Pocket USB 3.0 External Solid State Drive @ eTeknix
- Silicon Power Thunder T11 120 GB @ techPowerUp
- Silicon Power Armor A80 2TB USB 3.0 Portable Hard Drive Review @ NikKTech
- Patriot Memory Stellar Boost XT 64GB USB 3.0 OTG Drive Review @ Madshrimps
- Synology DiskStation DS1815+ @ Legion Hardware
- Western Digital Red Pro (WD4001FFSX) 4 TB @ Tech ARP
Subject: Storage | November 12, 2014 - 04:44 PM | Allyn Malventano
Tagged: ssd, pcie, NVMe, Intel, DC P3500
Since we reviewed the Intel SSD DC P3700, many of you have been drooling over the idea of an 18-channel NVMe PCIe SSD, even more so given that the P3500 variant was to launch at a $1.50/GB target price. It appears we are getting closer to that release, as the P3500 has been appearing on some web sites in pre-order or out of stock status.
ShopBLT lists the 400GB part at $629 ($1.57/GB), while Antares Pro has an out of stock listing at $611 ($1.53/GB). The other two capacities are available at a similar cost/GB. We were hoping to see an 800GB variant, but it appears Intel has stuck to their initial plan. Here are the part numbers we’ve gathered, for your Googling pleasure:
- 400GB: SSDPEDMX400G401
- 1.2TB: SSDPEDMX012T401
- 2TB: SSDPEDMX020T401
2.5” SFF-8639 (*not SATA*):
- 400GB: SSDPE2MX400G401
- 1.2TB: SSDPE2MX012T401
- 2TB: SSDPE2MX020T401
We did spot a date of December 12th in an Amazon listing, but I wouldn't count that as a solid date, as many of the listings there had errors (like 10 packs for the price of one).
Subject: Storage | November 11, 2014 - 05:32 PM | Allyn Malventano
Tagged: Intel, ssd, dc s3500, M.2
Today Intel refreshed their Datacenter Series of SSDs, specifically their DC S3500. We have reviewed this model in the past. It uses the same controller that is present in the S3700, as well as the SSD 730 Series (though it is overclocked in that series).
The full line of Intel Datacenter SSDs (minus the P3700). DC S3500 is just right of center.
Todays refresh includes higher capacities to the S3500, which now include 1.2TB and 1.6TB on the hign end of capacity. This suggests that Intel is stacking 20nm dies as many as 8 to a package. IOPS performance sees a slight penalty at these new higher capacities, while maximum sequentials are a bit higher due to the increased die count.
Also announced was an M.2 version of the S3500. This packaging is limited to only a few capacity points (80GB, 120GB, 340GB), and is p;rimarily meant for applications where data integrity is critical (i.e. ATM's, server boot partitions, etc).
A standard press blast was unavailable, but full specs are listed after the break.
Introduction, Specifications and Packaging
G.Skill is likely better known for their RAM offerings, but they have actually been in the SSD field since the early days. My first SSD RAID was on a pair of G.Skill Flash SSDs. While they were outmaneuvered by the X25-M, they were equipped with SLC flash, and G.Skill offered them at a significantly lower price than the Samsung OEM units they were based on.
Since those early days of flash, G.Skill has introduced a few additional models but has not been known as a major player in the SSD market. That is set to change today, with their introduction of the Phoenix Blade PCIe SSD:
If you're eager to know what is inside or how it works, I'll set your mind at ease with this brief summary. The Phoenix Blade is essentially an OCZ RevoDrive 350, but with beefier specs and improved performance. The same SandForce 2281 controllers and Toshiba flash are used. The difference comes in the form of a smaller form factor (half height vs. full height PCIe), and the type of PCIe to SATA bridge chip used. More on that on the disassembly page.
Given that we are anticipating a launch of the Samsung 850 EVO very shortly, it is a good time to back fill on the complete performance picture of the 850 Pro series. We have done several full capacity roundups of various SSD models over the past months, and the common theme with all of them is that as the die count is reduced in lower capacity models, so is the parallelism that can be achieved. This effect varies based on what type of flash memory die is used, but the end result is mostly an apparent reduction in write performance. Fueling this issue is the increase in flash memory die capacity over time.
There are two different ways to counteract the effects of write speed reductions caused by larger capacity / fewer dies:
- Reduce die capacity.
- Increase write performance per die.
Recently there has been a trend towards *lower* capacity dies. Micron makes their 16nm flash in both 128Gbit and 64Gbit. Shifting back towards the 64Gbit dies in lower capacity SSD models helps them keep the die count up, increasing overall parallelism, and therefore keeping write speeds and random IO performance relatively high.