Micron P400m SSD Review: High Endurance MLC Is Here To Stay

By Drew Riley
published

Endurance. Reliability. Data protection. They're all important factors when it comes time to evaluate high-end storage technology. Micron's P400m, the company's latest enterprise-class SSD, is positioned to not only address those needs, but exceed them.

Inside Micron's P400m SSD

The P400m's insides are pretty standard-looking. On one side of the PCB you find the controller, DRAM cache, some capacitors, and eight NAND packages. The bottom plays host to eight more memory packages.

Each package is composed of 25 nm MLC die manufactured by Micron. And although the company doesn't affix any special marketing terminology to the NAND itself (like eMLC or HET-MLC), company reps make it clear that this isn't the same stuff you'd find in a desktop drive. Micron is using extended-life, enterprise-rated MLC memory in the P400m. It's unique to the company's own SSDs, and not available to other vendors on the open market. 

Again, next to the controller you'll find 256 MB of Micron's DDR3 DRAM (2SD22-D9LGQ). So, all of the P400m's storage is manufactured by Micron.

On the other hand, the controller is a Marvell 88SS9187-BLD2, also found on Plextor's enthusiast-oriented M5 Pro. This eight-channel, dual-core ASIC connects to the host over a 6 Gb/s SATA interface. Even if the controller logic isn't Micron's own, the company did develop custom firmware written to specifically support its MLC NAND. The controller also has dedicated hardware buffers that help accelerate RAID calculations.

All together, Micron enjoys a higher degree of vertical integration than most SSD vendors achieve. What is it able to do with that advantage?

Drew Riley
16 Comments Comment from the forums
  • Nintendo Maniac 64
    に?

    Seriously though, I wonder why Tom's doesn't run one of their basic "real-world" tests used on consumer SSDs (such as Tom's 7zip test) on one of these professional SSDs just so that we can get an idea how they compare to the consumer-level stuff.

    In particular, Tom's always says that comparing one SSD to another is nearly moot point when you consider the magnitude of improvement an SSD has over a traditional HDD; it would be nice to know if these pro-level SSDs are of a similar magnitude of improvement over consumer SSDs or whether the difference is actually less.
    Reply
  • blazorthon
    Nintendo Maniac 64に?Seriously though, I wonder why Tom's doesn't run one of their basic "real-world" tests used on consumer SSDs (such as Tom's 7zip test) on one of these professional SSDs just so that we can get an idea how they compare to the consumer-level stuff.In particular, Tom's always says that comparing one SSD to another is nearly moot point when you consider the magnitude of improvement an SSD has over a traditional HDD; it would be nice to know if these pro-level SSDs are of a similar magnitude of improvement over consumer SSDs or whether the difference is actually less.
    The difference is much, much less in terms of performance difference. Tom's has told us this time and time again.
    Reply
  • mayankleoboy1
    Nintendo Maniac 64に?Seriously though, I wonder why Tom's doesn't run one of their basic "real-world" tests used on consumer SSDs (such as Tom's 7zip test) on one of these professional SSDs just so that we can get an idea how they compare to the consumer-level stuff.In particular, Tom's always says that comparing one SSD to another is nearly moot point when you consider the magnitude of improvement an SSD has over a traditional HDD; it would be nice to know if these pro-level SSDs are of a similar magnitude of improvement over consumer SSDs or whether the difference is actually less.
    In desktop loads, very very less difference.
    In server loads, huge difference. Plus, these server SSD's wil maintain high speeds even after large amounts of data is continuously being written.
    Reply
  • mayankleoboy1
    theoretical question : how much life would 100% provisioning give ? So you ship a 512GB MLC drive, but the usable is only 256GB. The rest 256GB is for getting better wrtite endurance.
    How would this compare to a true SLC SSD ?
    Reply
  • blazorthon
    mayankleoboy1theoretical question : how much life would 100% provisioning give ? So you ship a 512GB MLC drive, but the usable is only 256GB. The rest 256GB is for getting better wrtite endurance. How would this compare to a true SLC SSD ?
    It'd probably still be inferior overall and not even be cheaper at that point. Over-provisioning is only good for mitigating MLC's disadvantages over SLC AFAIK, not replacing SLC.
    Reply
  • blazorthon
    mayankleoboy1In desktop loads, very very less difference.In server loads, huge difference. Plus, these server SSD's wil maintain high speeds even after large amounts of data is continuously being written.
    Even in server workloads, there are many desktop drives where the performance difference is still not great. For example, Vector is right up there at the tops of the charts with Samsung 840 Pro in performance and many cheaper alternatives are often not far behind in performance. Endurance is another matter, but that wasn't the question. If you want a seriously significant performance difference like with HDDs versus cheap consumer SSDs, you have to consider SSD RAID and/or extreme PCIe storage.

    Also, many consumer drives have no trouble keeping performance over time with lots of data written. That's also not an enterprise-only feature.
    Reply
  • mayankleoboy1
    edit
    Reply
  • drewriley
    mayankleoboy1theoretical question : how much life would 100% provisioning give ? So you ship a 512GB MLC drive, but the usable is only 256GB. The rest 256GB is for getting better wrtite endurance. How would this compare to a true SLC SSD ?
    Some back of the napkin calculations - If you have a consumer 512GB MLC SSD with no over-provisioning, and the MLC was high grade consumer, you could expect 5K P/E cycles. In order to mimic the P400m, which is 35K P/E cycles, the usable space would be ~75GB. By dong that, you would be paying roughly $7/GB for usable storage(assuming you paid $512 for your consumer drive). For SLC, you are looking at 17GB of usable space and $30/GB.

    No matter how you look at it, consumer grade MLC will never get close to eMLC and SLC in terms of write endurance, unless the price goes down by orders of magnitude compared to eMLC and SLC.
    Reply
  • drewriley
    blazorthonEven in server workloads, there are many desktop drives where the performance difference is still not great. For example, Vector is right up there at the tops of the charts with Samsung 840 Pro in performance and many cheaper alternatives are often not far behind in performance. Endurance is another matter, but that wasn't the question. If you want a seriously significant performance difference like with HDDs versus cheap consumer SSDs, you have to consider SSD RAID and/or extreme PCIe storage.Also, many consumer drives have no trouble keeping performance over time with lots of data written. That's also not an enterprise-only feature.
    You are correct. Many drives, such as the 840 PRO, would perform great on the enterprise performance tests. There are also a lot of consumer drives that would have problems over time if they aren't allowed to TRIM every so often. We limit the scope of our testing because the main use cases for these drives are enterprise. Will some companies use them in workstations, absolutely. The same can be said for high-end RAID cards too. Nearly every consumer drive would perform very poorly when you take into account write endurance and other enterprise features.
    Reply
  • themdg
    This technology is moving so fast...hard to keep up. I feel like these articles could use that line from Tommy Boy and get the same point across (to me, at least).

    "These hard drives are really cool...you're not even gonna believe it..."
    Reply