Keming kemingy

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

Achieving warp speed with Rust

Swift Concurrency Manifesto

Author: Chris Lattner

Chinese Translation by Jason Yu

High-Performance Matrix Multiplication

This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).

Intro

Matrix multiplication is a mathematical operation that defines the product of

CUSTOM GAME ENGINES: A Small Study

WARNING: Article moved to separate repo to allow users contributions: https://github.com/raysan5/custom_game_engines

A couple of weeks ago I played (and finished) A Plague Tale, a game by Asobo Studio. I was really captivated by the game, not only by the beautiful graphics but also by the story and the locations in the game. I decided to investigate a bit about the game tech and I was surprised to see it was developed with a custom engine by a relatively small studio. I know there are some companies using custom engines but it's very difficult to find a detailed market study with that kind of information curated and updated. So this article.

Nowadays lots of companies choose engines like [Unreal](https:

hi, i'm daniel. i'm a 15-year-old with some programming experience and i do a little bug hunting in my free time. here's the insane story of how I found a single bug that affected over half of all Fortune 500 companies:

say hello to zendesk

If you've spent some time online, you’ve probably come across Zendesk.

Zendesk is a customer service tool used by some of the world’s top companies. It’s easy to set up: you link it to your company’s support email (like support@company.com), and Zendesk starts managing incoming emails and creating tickets. You can handle these tickets yourself or have a support team do it for you. Zendesk is a billion-dollar company, trusted by big names like Cloudflare.

Personally, I’ve always found it surprising that these massive companies, worth billions, rely on third-party tools like Zendesk instead of building their own in-house ticketing systems.

	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

	# maximum capability of system
	user@ubuntu:~$ cat /proc/sys/fs/file-max
	708444

	# available limit
	user@ubuntu:~$ ulimit -n
	1024

	# To increase the available limit to say 200000
	user@ubuntu:~$ sudo vim /etc/sysctl.conf

	# Example of two-line ZSH prompt with four components.
	#
	# top-left top-right
	# bottom-left bottom-right
	#
	# Components can be customized by editing set-prompt function.
	#
	# Installation:
	#
	# (cd && curl -fsSLO https://gist.githubusercontent.com/romkatv/2a107ef9314f0d5f76563725b42f7cab/raw/two-line-prompt.zsh)