SerCeMan

# Designing Data-Intensive Applications: The Big Ideas Behind Reliable, Scalable, and Maintainable Systems

1. **Chapter 1. Reliable, Scalable and Maintainable Applications**
  1. R faults != failures, faults cause failures. Systems should be fault-tolerant, resistant to some types of faults 
  2. S Amazon cares about 99.9% percentile because people with higher latencies usually are people who have the most data and therefore, they’re most valuable customers
  3. S tail latency amplification - multiple requests one critical path during one page served
2. **Chapter 2. Data Models and Query Languages**
  1. Hierarchical model - imperative querying, no way to change schema, children are ordered, no many-to-many
  2. CODASYL (network) vs SQL
  3. NoSQL - often no schema (precisely - schema on read vs schema on write)

SerCeMan

### Keybase proof

I hereby claim:

  * I am serceman on github.
  * I am serce (https://keybase.io/serce) on keybase.
  * I have a public key ASADB4KIVo7P2la3gA-uWScYnAc_gw8S2-LeRQc0O5SwQwo

To claim this, I am signing this object:

SerCeMan

(ns com.nda.myproduct
  (:require
    [clojure.tools.nrepl.server :as server]
    [clojure.tools.nrepl.middleware :as middleware]
    [clojure.tools.nrepl.middleware.session :as session]))

; util funcs
;...

SerCeMan

(ns clj-systemf.core)

(def => :to)

(defn type
  [term]
  (:type (meta term)))

(defn deftype [name]
  {:type :finite

SerCeMan

# Groovy
# For example, you can run it on groovyconsole.appspot.com

def s = /(\exists x P(x) \lor Q(x)) \to \exists x P(x) \lor \exists x Q(x)/
s = s.replace(/\vdash/, '|-')
s = s.replace(/\exists x/, 'exists x,')
s = s.replace(/\exists y/, 'exists y,')
s = s.replace(/\forall x/, 'forall x,')
s = s.replace(/\forall y/, 'forall y,')
s = s.replace(/\lor/, $/\//$)

SerCeMan

package ru.serce.gctest;

import java.lang.reflect.Method;

import javassist.ClassPool;
import javassist.CtClass;
import javassist.CtMethod;

public class GcPermgenTest {
    

SerCeMan

#!/usr/bin/python

# Quick and dirty demonstration of CVE-2014-0160 by Jared Stafford (jspenguin@jspenguin.org)
# The author disclaims copyright to this source code.

import sys
import struct
import socket
import time
import select

SerCeMan

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 * @author stselovalnikov

SerCeMan

set nocp
set number
set ignorecase
set expandtab
 
set tabstop=4       " The width of a TAB is set to 4.
set shiftwidth=4    " Indents will have a width of 4
set softtabstop=4   " Sets the number of columns for a TAB
set autoindent
 

SerCeMan

var yourId = 357957

var table = document.getElementById('apptable');
var rowLength = table.rows.length;

for(var i=1; i<rowLength; i+=1){
    var row = table.rows[i];
    var cellLength = row.cells.length;

    if(row.cells[0].childNodes[0].getAttribute('alt') === 'Unavailable') {