NVMe characteristics important to PrimoCache?
Posted: Mon Nov 20, 2023 11:38 pm
Hi All,
Looking to purchase a larger NVMe PCIe 4 disk to use as my PrimoCache disk. I had no idea previously how much detail in drive characteristics and capabilities there were to dig into here. NVMe controller, DRAM and NAND speeds are all huge factors in determining performance. No point having the fastest NAND if the controller can't supply the throughput, likewise no use having enormous NAND capacity if there is no DRAM to cache the I/0 as otherwise speeds can fall to SATA3 speeds (or less) as the disk gets fuller.
My first question is, what sort of performance is important to PrimoCache? Is random IO performance the most important, or does PrimoCache read/write from L1 and spinning disk to/from L2 cache in sequential reads and writes?
Second question. I've been told you should only partition NVMe drives to 80% of their capacity to ensure best performance as the drive fills and also to prevent excessive wear. Is this true and does this present any considerations for PrimoCache?
Looking to purchase a larger NVMe PCIe 4 disk to use as my PrimoCache disk. I had no idea previously how much detail in drive characteristics and capabilities there were to dig into here. NVMe controller, DRAM and NAND speeds are all huge factors in determining performance. No point having the fastest NAND if the controller can't supply the throughput, likewise no use having enormous NAND capacity if there is no DRAM to cache the I/0 as otherwise speeds can fall to SATA3 speeds (or less) as the disk gets fuller.
My first question is, what sort of performance is important to PrimoCache? Is random IO performance the most important, or does PrimoCache read/write from L1 and spinning disk to/from L2 cache in sequential reads and writes?
Second question. I've been told you should only partition NVMe drives to 80% of their capacity to ensure best performance as the drive fills and also to prevent excessive wear. Is this true and does this present any considerations for PrimoCache?