Some people measure "low latencies" in milliseconds. Typical for SSD-based databases. Some in microseconds. Appropriate for RAM-based systems. Others in nanos

Some people measure "low latencies" in milliseconds. Typical for SSD-based databases. Some in microseconds. Appropriate for RAM-based systems. Others in nanoseconds. I just spoke with an old friend at Cisco working with HFT switches. They're sampling data at the picosecond level. But the smallest time sampling I've personally run across was the 100 femtocecond level at SLAC. So there are utterly different orders of magnitude of scale when people talk about "fast" performance.