Latency numbers every programmer should know — Gist

Latency numbers every programmer should know — Gist:

L1 cache reference                          0.5 ns

Branch mispredict                             5 ns

L2 cache reference                            7 ns

Mutex lock/unlock                            25 ns

Main memory reference                       100 ns

Compress 1K bytes with Zippy              3,000 ns

Send 2K bytes over 1 Gbps network        20,000 ns

Read 1 MB sequentially from memory      250,000 ns

Round trip within same datacenter       500,000 ns

Disk seek                            10,000,000 ns

Read 1 MB sequentially from disk     20,000,000 ns

Send packet CA->Netherlands->CA     150,000,000 ns




By Jeff Dean (http://research.google.com/people/jeff/):