3 ms·
Is PCIe latency that much worse than main memory? I honestly don’t know; I was under the impression that both had latency in the 10s of nanoseconds.
by gok 9y ago
Is PCIe latency that much worse than main memory? I honestly don’t know; I was under the impression that both had latency in the 10s of nanoseconds.
- wtallis 9y agoNVMe devices using battery-backed DRAM or MRAM offer about 5µs access time, and current Optane SSDs are under 10µs. (NAND flash based SSDs with RAM-based write caches also have write latency below 10µs.)
- gok 9y agoSo is the bottleneck really NVMe? Could there be a different protocol over PCIe that had lower latency?
- wtallis 9y agoNVMe was more or less designed to offer the lowest possible latency for a block storage protocol. You could beat it with direct memory mapping, but then you're limiting compatibility to systems with working 64-bit I/O addressing and storage media that doesn't require complicated management like NAND flash does.
- Makepio 9y agoYou maybe consider about NVDIMM and persistent memory. But isn't available with consumer client products.