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Setup Postgresql

run postgresql with systemctl

Install postgres

latest

sudo pacman -S postgresql

specific version

find version & build from source

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

Updating expired GPG keys and their backup 🔑🔐💻

I use a GPG key to sign my git commits.

An error like this one might be a sign of an expired GPG key.

error: gpg failed to sign the data fatal: failed to write commit object

	import React, { useEffect, useState } from 'react';

	const InputDebounce = () => {

	const [text, setText] = useState('');

	useEffect(() => {
	const timeoutId = setTimeout(() => {
	console.log(text)
	//some function here

	Home/Core TX9XD-98N7V-6WMQ6-BX7FG-H8Q99
	Home/Core (Country Specific) PVMJN-6DFY6-9CCP6-7BKTT-D3WVR
	Home/Core (Single Language) 7HNRX-D7KGG-3K4RQ-4WPJ4-YTDFH
	Home/Core N 3KHY7-WNT83-DGQKR-F7HPR-844BM
	Professional W269N-WFGWX-YVC9B-4J6C9-T83GX
	Professional N MH37W-N47XK-V7XM9-C7227-GCQG9
	Professional Enterprise
	Professional Workstation
	Enterprise NPPR9-FWDCX-D2C8J-H872K-2YT43
	Enterprise N DPH2V-TTNVB-4X9Q3-TJR4H-KHJW4

	http://apassant.net/2012/01/16/timeout-for-html5-localstorage/

	var hours = 24; // Reset when storage is more than 24hours
	var now = new Date().getTime();
	var setupTime = localStorage.getItem('setupTime');
	if (setupTime == null) {
	localStorage.setItem('setupTime', now)
	} else {
	if(now-setupTime > hours6060*1000) {
	localStorage.clear()

	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

	# .bashrc essentials
	# copy and paste any parts that you need into your own ~/.bashrc

	# you may get a nicer one by default from your *nix distro; uncomment this
	# only if you have an ugly default "bash-x.y$" prompt string
	#PROMPT="[\u@\h:\w]$ "

	# trim the display of '\w' to just the last three path elements
	PROMPT_DIRTRIM=3

	#!/bin/bash
	# Automatic interactive installer for mtproto proxy https://github.com/seriyps/mtproto_proxy
	# Supported OS:
	# - Ubuntu 18.xx
	# - Ubuntu 19.xx
	# - Ubuntu 20.xx
	# - Ubuntu 21.xx
	# - Ubuntu 22.xx
	# - Debian 11 bullseye
	# - Debian 10 buster