Google Interview ( Time ) Part #1

Time of L1 cache reference ?
Answer: 0.5 ns.

Time of branch mis-predict ?
Answer: 5 ns.

 Time of L2 cache reference ?
Answer: 7 ns.

Time of mutex lock/unlock ?
Answer: 100 ns.

Time of main memory reference ?
Answer: 100 ns.

Time of compressing 1 kB with Zippy ?
Answer: 10 us.

Time of sending 2 kB over GigE ?
Answer: 20 us.

Time of reading 1 MB sequentially from memory ?
Answer: 250 us.

Round-trip time within same data center ?
Answer: 500 us.

Time of disk seek ?
Answer: 10 ms.

Time to read 1 MB sequentially from network ?
Answer: 10 ms.

Time to read 1 MB sequentially from disk ?
Answer: 30 ms.

RTT of packet from CA to Netherlands and back ?
Answer: 150 ms.

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