【Computer Science】知っておくべき数字一覧
· ☕ 1 min read
分岐予測の失敗 → 5ns L1 / L2キャッシュ→ 0.5ns / 7ns L1 cache reference 0.5 ns Branch mispredict 5 ns L2 cache reference 7 ns Mutex lock/unlock 100 ns Main memory reference 100 ns Compress 1K bytes with Zippy 10,000 ns 0.01 ms Send 1K bytes over 1 Gbps network 10,000 ns 0.01 ms Read 1 MB sequentially from memory 250,000 ns 0.25 ms Round trip within same datacenter 500,000 ns 0.5 ms Disk seek 10,000,000 ns 10 ms Read 1 MB sequentially from network 10,000,000 ns 10 ms Read 1 MB sequentially from disk 30,000,000 ns 30 ms Send packet CA->Netherlands->CA 150,000,000 ns 150 ms Where 1 ns = 10-9 seconds 1 ms = 10-3 seconds 引用: “Numbers Everyone Should Know” from Jeff Dean. doubleのbit数 MSB・指数・仮数で1 ...
