Intel Optane 905P 380GB M.2 Drive Performance
Intel Optane drives tend to put up awesome low queue depth numbers, and Intel usually specs them conservatively. Also, Optane uses 3D XPoint and can write in place unlike NAND and therefore also does not have big DRAM caches, most of the “exciting” read and write IOPS numbers are frankly less so versus traditional NAND devices. Instead of re-hashing Intel’s spec sheet, we wanted to show three use cases for the Intel Optane 905P where its costs may be justified. We are going to test under FreeBSD, Linux, and Windows just to ensure we get performance in some of the popular OSes that these will be deployed alongside.
Intel Optane 905P 380GB ZFS ZIL/ SLOG Test
Since the Intel Opatne 905P is rated at almost 7PBW, for most arrays it has enough endurance to serve as a ZIL or SLOG write logging device for ZFS. Again, see Exploring the Best ZFS ZIL SLOG SSD with Intel Optane and NAND for more on this. The key here is that the ZIL / SLOG device is a well-known write workload. So much so that exotic solutions like the ZeusRAM were developed years ago to do what Optane can do today. While many may assume it is a constant write, there is a slight difference. It instead writes for a period of time then flush pattern, not a constant write. For some perspective, the ZeusRAM drives were 8GB in capacity for large ZFS arrays.
First, here is a view using various SSDs with PLP that you may consider for a ZIL/ SLOG device with ZFS. We are going to express this in Mbytes/s:
There are two main comparisons you should look at. First, the Intel Optane 905P 380GB M.2 versus the two other M.2 22110 drives on this chart the SK.Hynix PE3110 960GB and the Samsung PM953 M.2 480GB SSD. The second is versus the Intel Optane 900p 280GB drive which was our first consumer Optane selected. We have a version of these charts with the P4800X AIC and you will see very similar trends.
Taking a look at the latency side, the Intel Optane drives are very hard to see.
We can zoom in on the chart’s smaller transfer sizes and get a better picture of what is going on.
The overall stratification here shows why you want Intel Optane versus SATA SSDs, SAS SSDs, and even over NAND NVMe SSDs. We are going to caveat this a bit. If you have a NAS with 1GbE or 10GbE, and say under 60TB that is more of a write once, read infrequently system, the Intel Optane 800P 118GB has enough endurance and performance to get you most of the benefits of Optane for 40% of the price. If you are thinking about deploying a 25GbE ZFS server and have a M.2 110mm slot to use for a SLOG device, this is what you want.
Intel Optane 905P Sub 1ms Latency
Intel Optane is too expensive to use for general purpose storage. For STH’s hosting cluster, all databases run on Optane, but our image and bulk hosting runs on NAND SSD arrays. There is a fairly easy way to visualize this using common iometer workloads. First, we are going to use our web server profile and look specifically at the sub 1ms service requests:
Here you can see a few trends. First, the Intel drives generally perform extremely well. Second, there is a delta between the Intel Optane DC P4800X and the Intel Optane 905P M.2. If you need the best performance and have the budget, you are better off with the Optane DC P4800X. The quick note here is that for web servers much of the data is primarily driven by reads, in which case modern web applications will cache in system RAM. For those applications, there is little need for an Optane SSD.
This is the chart which is why we use Optane for STH databases. You can see the performance figures are simply great for the Optane SSDs and translate to faster page views. Perhaps the bigger implication is looking at Optane versus other M.2 110mm SSDs which would previously had been your option outside of consumer drives without any PLP circuits.
Again, the Intel Optane 905P performs very well. staying above two nines throughout the range while the Samsung drives we used for these 110mm applications previously never achieves two nines of sub 1ms service requests. That is a big deal.
CrystalDiskMark 6 and Windows
Just to show this is not a one-trick pony for servers, we also fired up a Windows 10 Test Bed and let it run CrystalDiskMark 6.0.2 as a simple tool to show the more traditional figures. Here are the results:
Perhaps the biggest theme we are seeing is in the sequential numbers. The performance is slightly ahead of rated specs which seems to be a pattern with Intel Optane 900P and 905P SSDs in general.
For the vast majority of desktop workstation workloads, the Intel Optane 905P is overkill. It is hard to recommend a $500 380GB SSD in that space when there are 1TB and 2TB consumer NAND drives that will work perfectly well without the need for heavy sync writes.
At the same time, there are people who overbuild workstations to a large degree just because they can. Perhaps in those situations where one wants an Optane M.2 380GB drive instead of an Intel Optane 905P 1.5TB AIC model, it makes sense.
For server write workloads such as sync writes for databases and logging devices, Intel Optane is great.
If you have a workstation or a server with U.2 drive bays or PCIe AIC card slots, just get the larger form factors. For workstation and mobile users, there are better consumer drives that have more capacity out there. 380GB is still fairly small for modern systems. Frankly, there are a lot of use cases where the Intel Optane 905P 380GB M.2 drive is not the best fit, and there are other products in the Intel portfolio that will better service a user’s needs. In tight spaces, with limited PCIe slots such as our recent Gigabyte H261-Z60 server review and its 2U 4-node form factor, the Intel Optane 905P offers something much better than we had just a few weeks ago by making it plausible to use Optane in the systems.
With that out of the way, we are going to buy a ton of these drives for STH, and we need more than our budgets will allow. At around $500 for 380GB these drives are over $1.31/GB. Once capacity is reserved for snapshots and other modern storage features, that does not leave a ton of capacity for data and drives up the price of storage considerably while NAND SSDs are larger and are seeing rapidly falling prices as QLC is introduced. For databases, and write logging devices, the Intel Optane 905P 380GB is the drive to get hands-down. As a result, we have a number of servers at STH that will have these drives onboard in the near future.