L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns on recent CPU
L2 cache reference ........................... 7 ns 14x L1 cache
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy ............. 3,000 ns = 3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns = 20 µs
SSD random read ........................ 150,000 ns = 150 µs
Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs 4X memory
Round trip within same datacenter ...... 500,000 ns = 0.5 ms 20x datacenter roundtrip
Read 1 MB sequentially from SSD* ..... 1,000,000 ns = 1 ms 80x memory, 20X SSD
Disk seek ........................... 10,000,000 ns = 10 ms
Read 1 MB sequentially from disk .... 20,000,000 ns = 20 ms
Send packet CA->Netherlands->CA .... 150,000,000 ns = 150 ms
LTO4 tape seek/access time ...... 55.000.000.000 ns = 55 s