TylerBrock

hadoop jar mongo-hadoop-streaming-assembly*.jar -mapper mapper.rb -reducer reducer.rb -inputURI mongodb://127.0.0.1/twitter.in -outputURI mongodb://127.0.0.1/twitter.out

TylerBrock

/* sample aggregate command queries */
// make sure we're using the right db; this is the same as "use mydb;" in shell
db = db.getSisterDB("aggdb");

// just passing through fields
var p1 = db.runCommand(
{ aggregate : "article", pipeline : [
    { $project : {
	tags : 1,
	pageViews : 1

TylerBrock

// make sure we're using the right db; this is the same as "use aggdb;" in shell
db = db.getSiblingDB("aggdb");

// simple projection
var p1 = db.runCommand(
{ aggregate : "article", pipeline : [
    { $project : {
	tags : 1,
	pageViews : 1
    }}

TylerBrock

db.getSiblingDB("admin");

var databases = null;

databases = db.runCommand("listDatabases");

if(databases){

    for(var i=0;i<databases.databases.length;i++){
        //TODO skip if it's the admin database

TylerBrock

Latency Comparison Numbers
--------------------------
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
Send 1K bytes over 1 Gbps network        10,000   ns    0.01 ms
Read 4K randomly from SSD*              150,000   ns    0.15 ms

TylerBrock

db.getSiblingDB("admin");

var databases = null;

databases = db.runCommand("listDatabases");

if(databases){

    for(var i=0;i<databases.databases.length;i++){
        //TODO skip if it's the admin database

TylerBrock

#!/usr/bin/env mongo --quiet

var m = new Mongo();
var db = m.getDB('test');
var t = db.getCollection('whatever');

t.find( { group:3, 'x.a':1 }, { 'x.$':0 } );
printjson(db.getLastErrorCmd());
assert.eq( 16345, db.getLastErrorCmd().code, "exclusion of positional operator" ); 

TylerBrock

Wed Jul  4 13:23:37 [conn1587] end connection 127.0.0.1:50894 (5 connections now open)
Wed Jul  4 13:23:37 [conn1581] end connection 127.0.0.1:50888 (4 connections now open)
Wed Jul  4 13:23:37 [conn1589] end connection 127.0.0.1:50896 (3 connections now open)
Wed Jul  4 13:23:37 [conn1591] end connection 127.0.0.1:50898 (2 connections now open)
Wed Jul  4 13:23:42 [conn59] CMD fsync: sync:1 lock:1
Wed Jul  4 13:23:43 [fsyncLockWorker] removeJournalFiles
Wed Jul  4 13:23:43 [conn59] db is now locked for snapshotting, no writes allowed. db.fsyncUnlock() to unlock
Wed Jul  4 13:23:43 [conn59]     For more info see http://www.mongodb.org/display/DOCS/fsync+Command
Wed Jul  4 13:23:43 [conn59] command admin.$cmd command: { fsync: 1.0, lock: true } ntoreturn:1 keyUpdates:0 locks(micros) W:10958 r:1268 reslen:168 699ms
Wed Jul  4 13:23:44 [conn59] CMD fsync: sync:1 lock:1

TylerBrock

require 'mongo'
require './model/mongoModule'
require './model/user'

if ENV['RACK_ENV'] == 'production'
  CONNECTION = Mongo::Connection.from_uri(ENV['MONGOHQ_URL'])
else
  CONNECTION = Mongo::Connection.new("localhost", 27017)
end
DB         = CONNECTION.db('milieu')

TylerBrock

  class Monitor
    def initalize
      puts "whatup"
      @thread = Thread.new {
        loop do
          puts "ReplSetMonitor refreshing!"
          sleep(1)
        end
      }
    end