More consumer and prosumer-grade network attached storage (NAS) ship with the ability to accelerate workloads with SSDs. We can't pinpoint when the feature rolled out because the software feature was rolled out on existing products and not artificially limited to new models. Chances are, if you own a NAS manufactured in the last four years, the software supports using an SSD cache.
The latest cache acceleration feature from NAS manufactures is to expand the SSD options to include high-speed NVMe drives. Our QNAP TS-EC1279U-RP first reviewed here in May 2012 added this feature even though the system came to market long before the first NVMe SSD shipped. With NVMe and 40GbE network capabilities, we've increased our network storage performance significantly for a family of five uses the NAS as the backbone of our digital lives both at home and away on trips.
NVMe support in both M.2 and add-in card (AIC) form factors opens opportunities not available with SATA products. One of the most significant is Intel's Optane technology with a solid 3 to 4x increase in random read performance over existing flash technology. The same NVMe interface also opens the door to larger drives with stronger throughput performance that allows users to enable caching for sequential workloads to take better advantage of 10GbE network speeds.
Today we will use a Synology DS1819+ with a special dual M.2 2280 add-in card with two NVMe SSDs used as a read and write cache. We use Intel's 118GB Optane SSD and Samsung's 1TB 960 Pro flash-based SSD.
We used the Samsung 960 Pro, an older model that replaced by the new 970 Pro, because we needed two identical drives for the read + write cache test. We 960 Pro allows us to test large capacity MLC flash. The Samsung Pro series is the last from the MLC era, the market has moved on to TLC and even QLC memory technology.
On paper, the Intel 800P Optane shows lower random read performance and that is true, in a way. The 800P delivers higher random read IOPS at low queue depths, but the 960 Pro can scale better at high queue depths.
In the chart above we see the random read, write, and 80% mixed workload performance of the 120GB 800P and 1TB 960 Pro. At low queue depths, the 800P is significantly faster with random reads and mixed workloads. The Samsung 960 Pro is only moderately faster with random write performance.
What we want to do today is establish what NVMe SSD works better for accelerating a network storage workload. With this information, we can choose the product to use in all of our NAS reviews that don't specifically target the accelerator as the target of the review. For instance, in an upcoming review with a powerful enterprise NAS, we will compare the Intel Optane P4800X and Samsung 983 ZET (Z-NAND SSD). For our standard NAS reviews, we want to simply choose an option from the 800P and 960 Pro, to use in reviews like the upcoming Synology DS1819+.