Previewing Maxiotek's MK8115 SSD Controller: Can DRAM-less Drives Make The Cut?

ATTO

ATTO's Disk Benchmark is a quick and easy freeware tool to measure drive performance across various transfer sizes.

Maxiotek MK8115 512GB 3D MLCMaxiotek MK8115 512GB 3D TLCADATA Premier SP550 480GBADATA XPG SX930 480GBADATA Ultimate SU800 512GBCorsair Neutron XT 480GBCrucial BX100 500GBCrucial BX200 480GBCrucial MX100 512GBCrucial MX200 500GBCrucial MX300 525GBIntel 540s 480GBIntel SSD 600p 512GBOCZ RD400A 512GBOCZ Trion 100 480GBOCZ Trion 150 480GBOCZ Vector 180 480GBOCZ VX500 512GBPatriot Hellfire 480GBPlextor M8PeGN 512GB (M.2)Plextor M8PeY 512GBPNY CS1311 480GBPNY CS2211 480GBSamsung 850 EVO 500GBSamsung 850 Pro 512GBSamsung XP941 512GB (PCIe 2.0 x4 - AHCI)Samsung SM951 512GB (PCIe 3.0 x4 - AHCI)Samsung 950 Pro 512GBSanDisk Extreme Pro 480GBSilicon Motion SM2260 512GB 3D MLCToshiba Q300 480GBWD Black 512GB

Both MK8115 drives have horrible performance on 512-byte transfers, far lower than anything else we've tested in recent memory. Reads are more than 100 times slower for 512B than 1kB transfers, and for writes the difference is a factor of 24. Most filesystems use 4kB or larger block sizes, but 512B accesses are still common enough that this is a fairly severe bug that needs to be dealt with in future firmware.

Beyond 512B transfers, the TLC drive's write speed scales up quicker than the MLC drive, but its read speeds struggle a bit. For 128kB and larger transfers, both drives are operating at full speed and performing similarly to each other and most SATA drives.

AS-SSD

AS-SSD is another quick and free benchmark tool. It uses incompressible data for all of its tests, making it an easy way to keep an eye on which drives are relying on transparent data compression. The short duration of the test makes it a decent indicator of peak drive performance.

The MK8115 controller does make use of some compression, but its peak sequential read and writes speeds are not reliant upon the data being compressible. The MK8115 drives give AS-SSD performance that is typical for drives that are large enough to saturate the SATA link.

Idle Power Consumption

Since the ATSB tests based on real-world usage cut idle times short to 25ms, their power consumption scores paint an inaccurate picture of the relative suitability of drives for mobile use. During real-world client use, a solid state drive will spend far more time idle than actively processing commands. Our testbed doesn't support the deepest DevSlp power saving mode that SATA drives can implement, but we can measure the power usage in the intermediate slumber state where both the host and device ends of the SATA link enter a low-power state and the drive is free to engage its internal power savings measures.

We also report the drive's idle power consumption while the SATA link is active and not in any power saving state. Drives are required to be able to wake from the slumber state in under 10 milliseconds, but that still leaves plenty of room for them to add latency to a burst of I/O. Because of this, many desktops default to either not using SATA Aggressive Link Power Management (ALPM) at all or to only enable it partially without making use of the device-initiated power management (DIPM) capability. Additionally, SATA Hot-Swap is incompatible with the use of DIPM, so our SSD testbed usually has DIPM turned off during performance testing.

Idle power of the MK8115 is significantly improved over the JMF670H, but still lagging slightly behind the Phison-based PNY CS2211 and nowhere near the best SATA SSDs. Samsung and Marvell use more advanced lithography nodes for their controllers, and the smaller competitors on lagging fabrication processes can't beat them.

The active idle power consumption of the MK8115 drives is decent: it's clearly better than for the Silicon Motion drives or the OCZ VX500, but not quite as good as the Samsung and Marvell drives, nor the unusually efficient PNY CS2211.