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#!/bin/bash
#
# The reason of creating this script is that Endpoint Security VPN installs it's own application firewall kext cpfw.kext
# which prevents for example PPTP connections from this computer, which is not appropriate if you need subj connection just
# from time to time
#
# Usage: ./checkpoint.sh
#
# The script checks if Enpoint Security VPN is running. If it is, then it shuts it down, if it is not, it fires it up.
# Or, make an Automator action and paste the script.

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$> curl "https://gist.githubusercontent.com/pftg/fa8fe4ca2bb4638fbd19324376487f42/raw/f9056244c416d2f56d6d94290e5ecef5960abf66/rejuvenation.rb" | ruby

or

$> ruby rejuvenation.rb
$> yarn install

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require 'resque/tasks'

namespace :resque do
  def del(key)
    Resque.redis.keys(key).each { |k| Resque.redis.del(k) }
  end

  desc "Resque setup according to installation guide"
  task :setup => :environment

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version: '2'
services:
  api:
    volumes:
      - "nfsmount:${CONTAINER_DIR}"

volumes:
  nfsmount:
    driver: local
    driver_opts:

edgar

Backend Architectures

Twitter

ror, scala, jetty, erlang, thrift, mongrel, comet server, my-sql, memchached, varnish, kestrel(mq), starling, gizzard, cassandra, hadoop, vertica, munin, nagios, awstats

• Introduce Gizzard of Twitter - 트위터의 새로운 분산 관리 라이브러리 Gizzard를 소개합니다.
• The Architecture Twitter Uses to Deal with 150M Active Users, 300K QPS, a 22 MB/S Firehose, and Send Tweets in Under 5 Seconds
• Scaling Twitter: Making Twitter 10000 Percent Faster

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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

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Studying for a Tech Interview Sucks, so Here's a Cheat Sheet to Help

This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.

Data Structure Basics

###Array ####Definition:

• Stores data elements based on an sequential, most commonly 0 based, index.
• Based on tuples from set theory.

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// Includes functions for exporting active sheet or all sheets as JSON object (also Python object syntax compatible).
// Tweak the makePrettyJSON_ function to customize what kind of JSON to export.

var FORMAT_ONELINE   = 'One-line';
var FORMAT_MULTILINE = 'Multi-line';
var FORMAT_PRETTY    = 'Pretty';

var LANGUAGE_JS      = 'JavaScript';
var LANGUAGE_PYTHON  = 'Python';

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#!/usr/bin/env sh

# Download lists, unpack and filter, write to stdout
curl -s https://www.iblocklist.com/lists.php \
  | sed -n "s/.*value='\(http:.*=bt_.*\)'.*/\1/p" \
  | xargs wget -O - \
  | gunzip \
  | egrep -v '^#'

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