crazydogen

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
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

	// Here’s a 100% deterministic alternative to `Math.random`. Google’s V8 and
	// Octane benchmark suites use this to ensure predictable results.

	Math.random = (function() {
	var seed = 0x2F6E2B1;
	return function() {
	// Robert Jenkins’ 32 bit integer hash function
	seed = ((seed + 0x7ED55D16) + (seed << 12)) & 0xFFFFFFFF;
	seed = ((seed ^ 0xC761C23C) ^ (seed >>> 19)) & 0xFFFFFFFF;
	seed = ((seed + 0x165667B1) + (seed << 5)) & 0xFFFFFFFF;