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Benchmarking Nginx with Go

There are a lot of ways to serve a Go HTTP application. The best choices depend on each use case. Currently nginx looks to be the standard web server for every new project even though there are other great web servers as well. However, how much is the overhead of serving a Go application behind an nginx server? Do we need some nginx features (vhosts, load balancing, cache, etc) or can you serve directly from Go? If you need nginx, what is the fastest connection mechanism? This are the kind of questions I'm intended to answer here. The purpose of this benchmark is not to tell that Go is faster or slower than nginx. That would be stupid.

So, these are the different settings we are going to compare:

• Go HTTP standalone (as the control group)
• Nginx proxy to Go HTTP
• Nginx fastcgi to Go TCP FastCGI
• Nginx fastcgi to Go Unix Socket FastCGI

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Channels Are Not Enough

... or Why Pipelining Is Not That Easy

Golang Concurrency Patterns for brave and smart.

By @kachayev

Intro

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#System Design Interview Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

##Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

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import r from 'rethinkdb';
import config from '../config';

const createDatabase = (conn, name) =>
  r.dbList().contains(name)
    .do(containsDb =>
      r.branch(
        containsDb,
        { created: 0 },
        r.dbCreate(name)

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Next Steps

• Measure time spend on index, flush, refresh, merge, query, etc. (TD - done)
• Take hot threads snapshots under read+write, read-only, write-only (TD - done)
• Adjust refresh time to 10s (from 1s) and see how load changes (TD)
• Measure time of a rolling restart doing disable_flush and disable_recovery (TD)
• Specify routing on query -- make it choose same node for each shard each time (MD)
• GC new generation size (TD)
• Warmers

• measure before/after of client query time with and without warmers (MD)

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#MongoDB 3.2.x SSL with Letsencrypt Letsencrypt is an initative which aims to increase the use of encryption for websites. It basically allows people to apply for free certificates provided that they prove the they control the requested domain. We will look at the what is needed to secure your MongoDB installation. For more details on setting up a MongoDB server see MongoDB 3.2.x.

##Set the hostname We sould to set the hostname to match the name of the certificate we are going to optain.

sudo hostname mongo0.example.com

Then update the hostname file to set the server name permanently.

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*
!/.gitignore
!/*.xml
!/nextBuildNumber

!/jobs
!/jobs/*
!/jobs/*/*.xml
/jobs/*/disk-usage.xml
/jobs/*/builds

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# Delete the possibly existing autocomplete test index
curl -X DELETE localhost:9200/autocomplete_test

# Put the config of the autocomplete index
curl -X PUT localhost:9200/autocomplete_test -d '
{
  "settings" : {
    "index" : {
      "analysis" : {
        "analyzer" : {

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/*<?php
//*/public class PhpJava { public static void main(String[] args) { System.out.printf("/*%s",
//\u000A\u002F\u002A
class PhpJava {
    function main() {
        echo(//\u000A\u002A\u002F
        "Hello World!");
}}
//\u000A\u002F\u002A
PhpJava::main();

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There are three easy to make mistakes in go. I present them here in the way they are often found in the wild, not in the way that is easiest to understand.

All three of these mistakes have been made in Kubernetes code, getting past code review at least once each that I know of.

1. Loop variables are scoped outside the loop.

What do these lines do? Make predictions and then scroll down.

func print(pi *int) { fmt.Println(*pi) }