Latency Numbers Table

Operation Latency
L1 cache reference 1 nanosecond
CPU branch mispredict 3 nanoseconds
L2 cache reference 4 nanoseconds
Mutex Lock / Unlock 17 nanoseconds
Send 2000 bytes over commodity network 62 nanoseconds
Main memory / RAM reference 100 nanoseconds
Compress 1 KB with Zippy (Snappy) 2 microseconds
Read 1 million bytes sequentially from main memory 4 microseconds
Solid State Drive (SSD) random read 16 microseconds
Read 1 million bytes sequentially from SSD 62 microseconds
Read 1 million bytes sequentially from disk 947 microseconds
Round trip network request in same data centre 500 microseconds
Disk (Hard drive / magnetic drive) seek 3 milliseconds