yermulnik

git_protocol: ssh
aliases:
    personal: '!cp ~/.config/gh/hosts.yml.personal ~/.config/gh/hosts.yml && gh auth status'
    work: '!cp ~/.config/gh/hosts.yml.work ~/.config/gh/hosts.yml && gh auth status'

nadavrot

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

CMCDragonkai

Rust/Haskell: Higher-Kinded Types (HKT)

A higher kinded type is a concept that reifies a type constructor as an actual type.

A type constructor can be thought of in these analogies:

• like a function in the type universe
• as a type with a "hole" in it

lolzballs

import java.io.FileDescriptor;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;

public class HelloWorld{
	private static HelloWorld instance;
    public static void main(String[] args){
        instantiateHelloWorldMainClassAndRun();

felixjones

PMX (Polygon Model eXtended) 2.1

This is an English description of the .PMX file format used in Miku Miku Dance (MMD).

PMX is the successor to the .PMD format (Polygon Model Data).

This is work-in-progress! Please leave feedback in the comments.

Todo

ulrikdamm

# PMX 2.0 file format #

This is a description of the PMX file format. This is used for 3D models in Miku Miku Dance (MMD). 

Since I couldn't find any English descriptions of the PMX file format, I've made this, which is translated from http://gulshan-i-raz.geo.jp/labs/2012/10/17/pmx-format1/. I haven't used this file format yet, so please don't ask me what everything means.
An English guide to the PMD file format, which preceeded PMX, can be found here: http://mikumikudance.wikia.com/wiki/MMD:Polygon_Model_Data.

If you want to learn more, there are some open source projects on GitHub which can read this format, so go take a look at them.

Note: fields with type text begins with an int (32 bit) with how many bytes of text the section is.

jboner

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