Here is an essay version of my class notes from Class 1 of CS183: Startup. Errors and omissions are my own. Credit for good stuff is Peter’s entirely.
CS183: Startup—Notes Essay—The Challenge of the Future
Purpose and Preamble
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harperreed
/ peter-thiels-cs183-startup-class-01-notes-essay.md
Created
July 29, 2012 21:20
Notes Essays—Peter Thiel’s CS183: Startup—Stanford, Spring 2012
jboner
/ latency.txt
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October 31, 2025 03:43
Latency Numbers Every Programmer Should Know
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| Latency Comparison Numbers (~2012) | |
| ---------------------------------- | |
| L1 cache reference 0.5 ns | |
| Branch mispredict 5 ns | |
| L2 cache reference 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 | |
| Send 1K bytes over 1 Gbps network 10,000 ns 10 us | |
| Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD |
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