siburu

-module(qsort).
-export([qsort/1]).

% qsort/1
qsort([]) -> [];
qsort([Head|Rest]) ->
	{Less,Geq} = partition(Rest,Head),
	concat(qsort(Less), Head, qsort(Geq)).

% partition/2

siburu

-module(parse).
-export([parse/1]).

% parse("((1+2)*3)") => {mul,{add,{num,1},{num,2}},{num,3}}
parse(Str) ->
	{Parsed, []} = parse_addsub(nil, nil, skip_space(Str)),
	Parsed.

parse_addsub(Left, Op, Str) ->
	{Term, Rest} = parse_muldiv(nil, nil, Str),

siburu

#!/bin/sh

args=
afterj=false

for arg in $*
do
  if [ "$arg" = '-j' ]
  then
    afterj=true

siburu

Environment

• Google Compute Engine
• g1-small instance
• CentOS7 image (provided by Google Cloud Platform)

Incident

I created an instance and then executed the following commands:

$ sudo yum update
$ curl -O http://packages.treasuredata.com/2/redhat/6/x86_64/td-agent-2.1.0-0.x86_64.rpm

siburu

console.log('MAX_SAFE_INTEGER is ' + Number.MAX_SAFE_INTEGER);

let i = Number.MAX_SAFE_INTEGER - 100;
while (i + 1 > i) { i = i + 1; }

console.log('True max integer is ' + i);
console.log('Overflowed integer is ' + (i + 1));

siburu

package main

import "net/http"

func main() {
	http.ListenAndServe(":8080", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("HELLO!!!"))
	}))
}

siburu

package main

import (
	"fmt"
	"log"
	"syscall"
)

const filePath = "data.dat"

siburu

/*
A HTTP*S* server.
The path /ws is special, dedicated for WebSocket connection.
The other paths work as ordinary (non-WebSocket) resource.
*/

package main

import (
	"crypto/tls"

siburu

#!/bin/sh
# This script explains how to generate a self signed certificate (DER format).

if [ $# = 0 ]
then
	echo 'Usage: $0 <name>'
	exit 1
fi
name=$1

siburu

Must configure

sudo sysctl -w net.core.somaxconn=65535
sudo sysctl -w net.ipv4.tcp_max_syn_backlog=65535

Also important

net.ipv4.tcp_syncookies