Javito cheiff

tmux cheat sheet

(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

remap prefix to Control + a

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

Add this in your ini file:

[alembic:exclude]
tables = spatial_ref_sys

In env.py:

    import re

UFW

I use Ubuntu’s Uncomplicated firewall because it is available on Ubuntu and it's very simple.

Install UFW

if ufw is not installed by default be sure to install it first.

Background

While I'm learning how to use Nginx, I was instructed to update the server_names_hash_bucket_size (/etc/nginx/nginx.conf) value from 32 to 64, but I don't understand why should I increase the value to 64.

References

References that have been read so far:

See the Server names, Optimization section.
See setting up hashes

	<?php

	$countries = array
	(
	'AF' => 'Afghanistan',
	'AX' => 'Aland Islands',
	'AL' => 'Albania',
	'DZ' => 'Algeria',
	'AS' => 'American Samoa',
	'AD' => 'Andorra',

	haiku = ->
	adjs = [
	"autumn", "hidden", "bitter", "misty", "silent", "empty", "dry", "dark",
	"summer", "icy", "delicate", "quiet", "white", "cool", "spring", "winter",
	"patient", "twilight", "dawn", "crimson", "wispy", "weathered", "blue",
	"billowing", "broken", "cold", "damp", "falling", "frosty", "green",
	"long", "late", "lingering", "bold", "little", "morning", "muddy", "old",
	"red", "rough", "still", "small", "sparkling", "throbbing", "shy",
	"wandering", "withered", "wild", "black", "young", "holy", "solitary",
	"fragrant", "aged", "snowy", "proud", "floral", "restless", "divine",

	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

	<!doctype html>
	<title>Site Maintenance</title>
	<style>
	body { text-align: center; padding: 150px; }
	h1 { font-size: 50px; }
	body { font: 20px Helvetica, sans-serif; color: #333; }
	article { display: block; text-align: left; width: 650px; margin: 0 auto; }
	a { color: #dc8100; text-decoration: none; }
	a:hover { color: #333; text-decoration: none; }
	</style>

	# Make sure the ngx_http_stub_status_module is installed correctly.
	location /status {
	add_header Content-Type application/json;
	return 200 '{\r
	"connections_active": $connections_active,\r
	"connections_reading": $connections_reading,\r
	"connections_writing": $connections_writing,\r
	"connections_waiting": $connections_waiting
	}';
	}