Write Pressure, Conclusion, Pricing, and Final Thoughts
Before we wrap up, I wanted to reiterate and expand on a chart that Intel showed us at our briefing:
Since we had an additional comparison point and some increased testing flexibility on our end…:
I've added in the Micron 9100 MAX, which is able to achieve a higher random write load (300,000 IOPS) while still servicing reads, but we can certainly see the penalty adds up as the average latency climbs to over 1ms. The P3700 runs out of steam at 100,000 IOPS, but this was only a 800GB sample and was not able to reach the 750 MB/s seen with Intel's data above. All the while, check out that blue line down there. Intel only took their chart out to the ~200,000 random write IOPS point. I pushed the P4800X all the way past 500,000 random write IOPS and it was still able to service reads at just
36 24us, which I should point out is still quicker than the average read latencies of both competing products with no writes taking place at all (far left)!
- Outstanding random performance
- Outstanding QoS
- Outstanding endurance (based on rating)
- It's the fastest thing we've ever tested. Period.
- Cost (see below)
- Micron 9100 MAX (highest performing competing NAND Flash)
- 375GB: $1520 ($4.05/GB)
- 750GB: $3040 ($4.05/GB)
- P4800X IMDT w/ Intel Memory Drive Technology (augments/expands DRAM):
- add $862 to the above, and note that available capacity reduces to 320GB/640GB.
- Server-class ECC Registered DRAM:
Yes, this is expensive, but you definitely get what you pay for here, especially if your use case meshes nicely with where the P4800X shines. For your money, you are getting a product that eats random IOPS for breakfast, lunch, and dinner. And then it asks for dessert. Just don't waste your cash on this type of product unless you intend to use it for its designed purpose! Sure pretty much any IO heavy application will benefit greatly from the P4800X, but as with any storage system, you have to balance cost with performance. That second, more expensive tier of the P4800X includes a license for Intel MDT, which effectively converts the installed server RAM into a pool of Optane with the installed RAM acting as an additional cache layer. For many workloads, the MDT solution will offer similar performance at a substantial cost reduction over a pure RAM solution.
Warning (to non-IT pros):
If you have read this far and are not an enterprise customer, I know what you're thinking. You may want one of these for your video editing, workstation, or maybe even your gaming rig. That's fine, but there are a few things you need to consider. First, enterprise parts are tuned for random access across the entire drive, meaning a consumer SSD / firmware would likely perform better with consumer workloads as it is tuned for that purpose. Second, and more important in the case of Intel Datacenter parts, is the matter of 'assertion'. IT specialists don't like wasting time on intermittent faults and silent data corruption. If something is wrong in the slightest, an IT Pro just wants the thing to fail hard so they can replace it and get that portion of their network back up ASAP. As such, Intel programs their DC SSD firmware to enter an 'assert mode' at the slightest sign of trouble. An asserted Intel SSD is effectively a bricked SSD that won't do anything further as it is meant to be replaced. Even if most of the data was good, it will no longer be readable. That's not to say Intel's Datacenter SSDs are bricking left and right, but an SSD 750 (consumer version of the P3xxx) will push through many faults and attempt to continue operating while those same issues would instantly assert a P3520. Moral of the story – don't use an enterprise part for consumer purposes unless you are employing an enterprise-level redundancy / backup regime. Long story short, just stick with the 900P for those use cases!
I said it before and I'll say it again – the P4800X is a beast. It offers 10x the IOPS of competing NAND products at lower queue depths and services those requests in 1/10th of the time. Endurance is leaps and bounds above anything NAND flash can offer. The 750GB capacity showed no signs of weakness compared with the previously tested 375GB model. We are of course still running up against inefficiencies with IRQ-based storage requests. While Windows may catch up to Optane's speed someday, Linux has been steadily improving their kernel by adding block polling support in 4.4 and hybrid polling (more CPU efficient) in 4.10. We touched on the differences between IRQ and application-level polling under Windows in this review, and in the near future we will detail the further advantages to be had by using Optane on a Linux platform (spoiler – those 15us/10us Windows figures start looking more like 11us/7us on a better-optimized platform). More on that later, but for now I will part by saying that the in-hand product sample performed even better than the prototype unit we tested just a few short months ago. Higher capacities are launching now and in the near future, and the P4800X is clearly ready for prime time.
We couldn't previously award Editor's Choice to a product tested outside of our full control. This newer testing was all in-house, and given the performance of the P4800X, it's a no-brainer.