

Numbers Everyone Should Know (From Google Fellow Jeff Dean at LADIS09) [pdf] - yarapavan
http://www.cs.cornell.edu/projects/ladis2009/talks/dean-keynote-ladis2009.pdf

======
yarapavan
Jeff Dean reveals that a Google web search touches 50+ separate services,
1000s machines.

Again, from Slide No. 24 from the LADIS09 talk:

Numbers Everyone 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_

 _Send 2K bytes over 1 Gbps network 20,000 ns_

 _Read 1 MB sequentially from memory 250,000 ns_

 _Round trip within same datacenter 500,000 ns_

 _Disk seek 10,000,000 ns_

 _Read 1 MB sequentially from disk 20,000,000 ns_

 _Send packet CA- >Netherlands->CA 150,000,000 ns_

