| Name | |||||||
|---|---|---|---|---|---|---|---|
| L1 cache reference | 0.5 | ns | |||||
| Branch mispredict | 5 | ns | |||||
| L2 cachereference | 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 | us | ~330MB/sec | ||
| Send 1K bytes over 1 Gb ps network | 10,000 | ns | 10 | us | ~100MB/sec | ||
| Read 4K randomly from SSD | 150,000 | ns | 150 | us | 0.15 | ms | ~1GB/sec SSD |
| Read 1 MB sequentially from memory | 250,000 | ns | 250 | us | 0.2 | ms | ~4GB/sec |
| Round trip within same datacenter | 500,000 | ns | 500 | us | 0.5 | ms | |
| Read 1 MB sequentially from SSD | 1,000,000 | ns | 1,000 | us | 1 | ms | ~1GB/sec SSD, 4X memory |
| Disk seek | 10,000,000 | ns | 10,000 | us | 10 | ms | 20x datacenter roundtrip |
| Read 1 MB sequentially | 20,000,000 | ns | 20,000 | us | 20 | ms | 80x memory, 20X SSD |
| Send pack et CA->Netherlands->CA | 150,000,000 | ns | 150,000 | us | 150 | ms |
1 ns = 10^-9 seconds
1 us = 10^-6 seconds = 1,000 ns
1 ms = 10^-3 seconds = 1,000 us = 1,000,000 ns
By Jeff Dean: http://research.google.com/people/jeff/
Originally by Peter Norvig: http://norvig.com/21-days.html#answers
Original: https://gist.github.com/jboner/2841832
‘Humanized’ comparison: https://gist.github.com/hellerbarde/2843375
Visual comparison chart: http://i.imgur.com/k0t1e.png
