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@wronk
wronk / python_environment_setup.md
Last active April 10, 2025 22:25
Setting up your python development environment (with pyenv, virtualenv, and virtualenvwrapper)

Overview of Python Virtual Environments

This guide is targetted at intermediate or expert users who want low-level control over their Python environments.

When you're working on multiple coding projects, you might want a couple different version of Python and/or modules installed. This helps keep each workflow in its own sandbox instead of trying to juggle multiple projects (each with different dependencies) on your system's version of Python. The guide here covers one way to handle multiple Python versions and Python environments on your own (i.e., without a package manager like conda). See the Using the workflow section to view the end result.


h/t @sharkinsspatial for linking me to the perfect cartoon

@jboner
jboner / latency.txt
Last active October 3, 2025 03:33
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
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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