4 ms·
It can burst to millions of IOPS, but you get killed on the sustained write workload. Even a high end enterprise NVMe drive will be limited to around 60k IOPs
by jdsully 6y ago
It can burst to millions of IOPS, but you get killed on the sustained write workload. Even a high end enterprise NVMe drive will be limited to around 60k IOPs once you exceed its write cache.
- tanelpoder 6y agoYup indeed it's an issue with NAND SSDs - and it heavily depends on the type (SLC, MLC, TLC, QLC), vendor (controller, memory, "write buffer") sizes etc. I'm doing mostly read tests right now and will move to writes after. The Samsung PRO 980 I have, are TLC for main storage, but apparently are using some of that TLC storage as a faster write buffer (TurboWrite buffer) - I'm not an expert, but apparently the controller can decide to program the TLC NAND with only 1-bit "depth", they call it "simulated SLC" or something like that. On the 1 TB SSD, the turbowrite buffer can dynamically extend to ~100 GB, if there's unused NAND space on the disk. Btw, the 3DXpoint storage (Intel Optane SSDs & Micron X1) should be able to sustain crazy write rates too.