nijikokun

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns                     on recent CPU
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 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 4X memory

nijikokun

require 'formula'

class Vim < Formula
  homepage 'http://www.vim.org/'
  url 'https://vim.googlecode.com/hg/', :revision => '34a3b852ec05'
  version '7.4.091'

  def features; %w(tiny small normal big huge) end
  def interp; %w(lua mzscheme perl python python3 tcl ruby) end

nijikokun

G-WAN is a new free web server. They seem to be very proud of it, or at least just want to make a lot of money. Well anyway, in almost every sentence they write, they claim that they are 20% cooler than anything else. It feels a bit arrogant. I have to admit, I don't know a lot about web servers, so I can't speak to how good they are.

However, then I saw their Captcha example. I also don't know much about machine learning algorithms, OCR, and stuff like that, but I do know how to read pixels. I also know how to compare values with python :P

They say the following about their Captcha:

nijikokun

import java.util.Map;

public class Main {
    static Map<Object,Object> map;
    
    public static void main(String[] args) {
        if(map == null) {
            System.out.println("test");
        }
    }