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@timothyham
timothyham / ipv6guide.md
Last active September 23, 2024 22:28
A Short IPv6 Guide for Home IPv4 Admins

A Short IPv6 Guide for Home IPv4 Admins

This guide is for homelab admins who understand IPv4s well but find setting up IPv6 hard or annoying because things work differently. In some ways, managing an IPv6 network can be simpler than IPv4, one just needs to learn some new concepts and discard some old ones.

Let’s begin.

First of all, there are some concepts that one must unlearn from ipv4:

Concept 1

@seanh
seanh / netrw.md
Last active September 19, 2024 17:25
Netrw Cheatsheet (Vim's Built-in Directory Browser)

Netrw Cheatsheet (Vim's File Browser)

See also:

  • vinegar.vim, which makes - open netrw in the directory of the current file, with the cursor on the current file (and pressing - again goes up a directory). Vinegar also hides a bunch of junk that's normally at the top of netrw windows, changes the default order of files, and hides files that match wildignore.

    With vinegar, . in netrw opens Vim's command line with the path to the file under the cursor at the end of the command. ! does the same but also prepends ! at the start of the command. y. copies the absolute path of the file under the cursor. ~ goes to your home dir. Ctrl+6 goes back to the file (buffer) that you had open before you opened netrw.

To launch netrw:

@josephwecker
josephwecker / new_bashrc.sh
Created August 11, 2012 04:36
Replace .bashrc, .bash_profile, .profile, etc. with something much more clean, consistent, and meaningful. Now a repo: https://github.com/josephwecker/bashrc_dispatch
#!/bin/bash
# License: Public Domain.
# Author: Joseph Wecker, 2012
#
# -- DEPRICATED --
# This gist is slow and is missing .bashrc_once
# Use the one in the repo instead! https://github.com/josephwecker/bashrc_dispatch
# (Thanks gioele)
#
# Are you tired of trying to remember what .bashrc does vs .bash_profile vs .profile?
@jboner
jboner / latency.txt
Last active September 25, 2024 13:05
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