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@jstn
jstn / Timer.swift
Last active June 19, 2022 15:14
simple nanosecond timer using mach_absolute_time
/*
var t = Timer()
t.start()
// do something
t.stop()
print("took \(t.seconds)")
*/
@marktheunissen
marktheunissen / pedantically_commented_playbook.yml
Last active August 25, 2025 12:52 — forked from phred/pedantically_commented_playbook.yml
Insanely complete Ansible playbook, showing off all the options
This playbook has been removed as it is now very outdated.
@jboner
jboner / latency.txt
Last active October 21, 2025 18:15
Latency Numbers Every Programmer Should Know
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