ijt

package main

import (
        "fmt"
        "io"
        "log"
        "net/http"
        "os"
)

grantr

## mysql::master
ruby_block "store_mysql_master_status" do
  block do
    node.set[:mysql][:master] = true
    m = Mysql.new("localhost", "root", node[:mysql][:server_root_password])
    m.query("show master status") do |row|
      row.each_hash do |h|
        node.set[:mysql][:master_file] = h['File']
        node.set[:mysql][:master_position] = h['Position']
      end

rtomayko

#!/usr/bin/env ruby
#/ Usage: <progname> [options]...
#/ How does this script make my life easier?
# ** Tip: use #/ lines to define the --help usage message.
$stderr.sync = true
require 'optparse'

# default options
flag    = false
option  = "default value"

vmihailenco

package main

import (
	"bytes"
	"encoding/hex"
	"flag"
	"fmt"
	"io"
	"log"
	"net"

jordansissel

Logstash internals (Queues and Threading)

The logstash agent is 3 parts: inputs -> filters -> outputs.

Each '->' is an internal messaging system. It is implemented with a 'SizedQueue' in Ruby. SizedQueue allows a bounded maximum of items in the queue such that any writes to the queue will block if the queue is full at maximum capacity.

Logstash sets the queue size to 20. This means only 20 events can be pending into the next phase - this helps reduce any data loss and in general avoids logstash trying to act as a data storage system. These internal queues are not for storing messages long-term.

In reverse, here's what happens with a queue fills.

saetia

OS X Preferences

---

most of these require logout/restart to take effect

# Enable character repeat on keydown
defaults write -g ApplePressAndHoldEnabled -bool false

# Set a shorter Delay until key repeat

bemasher

package main

import (
	"fmt"
)

type Stack struct {
	top *Element
	size int
}

bmc

module RFC1918
  def is_rfc1918_address(ip)
    unless ip =~ /^(\d{1,3}).(\d{1,3}).(\d{1,3}).(\d{1,3})$/
      raise "#{ip} is not an IP address"
    end

    octets = [$1, $2, $3, $4].map &:to_i
    raise "#{ip} is a bad IP address" unless octets.all? {|o| o < 256}

    # The Internet Assigned Numbers Authority (IANA) has reserved the

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

hellerbarde

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