L1 cache reference                  0.5 ns               1 sec
Branch mispredict                   5 ns                10 sec
L2 cache reference                  7 ns                14 sec
Mutex lock/unlock                   25 ns               50 sec
Main memory reference               100 ns             3.3 min
Compress 1K bytes with Zippy        3,000 ns           1.7 hr
Send 2K bytes over 1 Gbps network   20,000 ns         11.0 hr
Read 1 MB sequentially from memory  250,000 ns         5.8 days
Round trip within same datacenter   500,000 ns        11.6 days
Disk seek                           10,000,000 ns      7.7 months
Read 1 MB sequentially from disk    20,000,000 ns     15.4 months
Send packet CA->Netherlands->CA     150,000,000 ns     9.5 years