The Computer Latency Calendar

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I recently saw this Gist and Interactive Page, so I thought it would be cool to update it for the 2020s. This can serve as a visualization of how fast a modern computer is.

How to read this calendar

Imagine 1 CPU cycle took 1 second. Compared to that, A modern 4.0 GHz CPU has a CPU cycle of 0.25 ns approx. That's 4,000,000,000 times difference. Now, imagine how that CPU would feel one second in real life.

Action	Physical Time	CPU Time
1 CPU Cycle	0.25ns	1 second
L1 cache reference	1ns	4 seconds
Branch mispredict	3ns	12 seconds
L2 cache reference	4ns	16 seconds
Mutex lock	17ns	68 seconds
Send 2KB	44ns	2.93 minutes
Main memory reference	100ns	6.67 minutes
Compress 1KB	2μs	2.22 hours
Read 1MB from memory	3μs	3.33 hours
SSD random read	16μs	17.78 hours
Read 1MB from SSD	49μs	2.27 days
Round trip in the same data center	500μs	23.15 days
Read 1MB from the disk	825μs	38.20 days
Disk seek	2ms	92.60 days
Packet roundtrip from California to Seoul	200ms	25.35 years
OS virtualization reboot	5s	633 years
SCSI command timeout	30s	3,802 years
Hardware virtualization reboot	40s	5,070 years
Physical system reboot	5m	38,026 years

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