kedarmhaswade

/**
 * This program tries to demonstrate the surprising sequential consistency.
 * A program is sequentially consistent as long as calls made in a single
 * thread follow the program order. Program order however, does not apply
 * to the executions across threads.
 * It's hard to demonstrate that a counterintuitive behavior might actually
 * be sequentially consistent. Let's say, we have a FIFO queue, q and two threads: A, B
 *
 * Thread A does:
 *   q.enq(x); returns at time 1.

kedarmhaswade

  find: function(req, res) {
    Items.find().done(function (err, val) {
      if (err) {
        res.send(err);
      }
      res.send(val);
    });
  },

kedarmhaswade

  module.exports = {
//...
  find: function(req, res) {
    Items
        .find()
        .exec(function(err, items) {
          if (err) {
            res.send(err);
          } else if (items) {
            items.forEach(

kedarmhaswade

  all: function(params, callback) {
    var async = require('async');
    var reviews = null;
    async.series([
      function load_reviews(cb) {
        Reviews.find().exec(function (err, result) {
          reviews = result;
          cb(null, reviews);
        });
      },

kedarmhaswade

    Sep 14 15:50:34 mypc NetworkManager[736]: <info> Activation (wlan0) starting connection 'LessWire'
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> (wlan0): device state change: disconnected -> prepare (reason 'none') [30 40 0]
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> NetworkManager state is now CONNECTING
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) scheduled...
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) started...
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) scheduled...
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) complete.
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) starting...
    Sep 14 15:50:34 mypc NetworkManager[736]: <info> (wlan0): device state change: prepare -> config (reason 'none') [40 50

kedarmhaswade

Sep 14 20:18:40 mypc kernel: [ 1241.379380] Intel(R) Wireless WiFi driver for Linux, in-tree:
Sep 14 20:18:40 mypc kernel: [ 1241.379383] Copyright(c) 2003-2013 Intel Corporation
Sep 14 20:18:40 mypc kernel: [ 1241.379429] iwlwifi 0000:02:00.0: enabling device (0000 -> 0002)
Sep 14 20:18:40 mypc kernel: [ 1241.379505] iwlwifi 0000:02:00.0: can't disable ASPM; OS doesn't have ASPM control
Sep 14 20:18:40 mypc kernel: [ 1241.379576] iwlwifi 0000:02:00.0: irq 51 for MSI/MSI-X
Sep 14 20:18:40 mypc kernel: [ 1241.380366] iwlwifi 0000:02:00.0: loaded firmware version 41.28.5.1 build 33926 op_mode iwldvm
Sep 14 20:18:40 mypc kernel: [ 1241.409982] iwlwifi 0000:02:00.0: CONFIG_IWLWIFI_DEBUG disabled
Sep 14 20:18:40 mypc kernel: [ 1241.409987] iwlwifi 0000:02:00.0: CONFIG_IWLWIFI_DEBUGFS enabled
Sep 14 20:18:40 mypc kernel: [ 1241.409988] iwlwifi 0000:02:00.0: CONFIG_IWLWIFI_DEVICE_TRACING enabled
Sep 14 20:18:40 mypc kernel: [ 1241.409990] iwlwifi 0000:02:00.0: Detected Intel(R) Centrino(R) Wireless-N + WiMAX 6150 BG

kedarmhaswade

filename:       /lib/modules/3.13.0-24-generic/kernel/drivers/net/wireless/iwlwifi/iwlwifi.ko
license:        GPL
author:         Copyright(c) 2003-2013 Intel Corporation <ilw@linux.intel.com>
version:        in-tree:
description:    Intel(R) Wireless WiFi driver for Linux
firmware:       iwlwifi-100-5.ucode
firmware:       iwlwifi-1000-5.ucode
firmware:       iwlwifi-135-6.ucode
firmware:       iwlwifi-105-6.ucode
firmware:       iwlwifi-2030-6.ucode

kedarmhaswade

Sep 16 20:12:13 mypc wpa_supplicant[905]: wlan0: CTRL-EVENT-SCAN-STARTED 
Sep 16 20:12:14 mypc wpa_supplicant[905]: nl80211: send_and_recv->nl_recvmsgs failed: -33
Sep 16 20:12:32 mypc kernel: [  711.959905] cfg80211: Calling CRDA for country: US
Sep 16 20:12:32 mypc kernel: [  711.962582] cfg80211: Regulatory domain changed to country: US
Sep 16 20:12:32 mypc kernel: [  711.962585] cfg80211:  DFS Master region: unset
Sep 16 20:12:32 mypc kernel: [  711.962586] cfg80211:   (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Sep 16 20:12:32 mypc kernel: [  711.962588] cfg80211:   (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2700 mBm)
Sep 16 20:12:32 mypc kernel: [  711.962589] cfg80211:   (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 1700 mBm)
Sep 16 20:12:32 mypc kernel: [  711.962591] cfg80211:   (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Sep 16 20:12:32 mypc kernel: [  711.962592] cfg80211:   (5490000 KHz - 5600000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)

kedarmhaswade

Experiment a billion times:

➜  combinatorial-algorithms git:(master) ✗ java -ea RandomSubset 4 1000000000




Frequencies of chosen subsets ....
                 [3] :   68566736, 6.856674
                  [] :   79538193, 7.953819

kedarmhaswade

/**
 * Problem: Print the statistics of RandomSubset algorithm when the experiment
 * of choosing a subset at random is done the specified number of times.
 */
import java.util.*;
class RandomSubsetSimulation {
  static final Random r = new Random(System.currentTimeMillis()); //fix for the bug in the SO thread (see below)
  public static void main(String[] args) { 
    // arg[0] = the max number n in the set: {1, 2, 3, ... n}
    // arg[1] = the number of times the experiment is to be done