SSD · solid-state drive
Flash-based storage with no moving parts, the default medium for the node-local scratch and checkpoint tiers where sustained per-drive bandwidth matters more than capacity cost.
Current numbers
~28 / 14 GB/sPCIe 6.0 x4 enterprise SSD sequential read/write (Micron 9650, first Gen6 in mass production), ~5.5M IOPS; E1.S & E3.S
~7 GB/s vs ~300 MB/sQLC SSD vs HDD sequential read; 20–100 µs vs ~4 ms latency