joewiz

On Tue Oct 27, 2015, history.state.gov began buckling under load, intermittently issuing 500 errors. Nginx's error log was sprinkled with the following errors:

2015/10/27 21:48:36 [crit] 2475#0: accept4() failed (24: Too many open files)

2015/10/27 21:48:36 [alert] 2475#0: *7163915 socket() failed (24: Too many open files) while connecting to upstream...

An article at http://www.cyberciti.biz/faq/linux-unix-nginx-too-many-open-files/ provided directions that mostly worked. Below are the steps we followed. The steps that diverged from the article's directions are marked with an *.

1. * Instead of using su to run ulimit on the nginx account, use ps aux | grep nginx to locate nginx's process IDs. Then query each process's file handle limits using cat /proc/pid/limits (where pid is the process id retrieved from ps). (Note: sudo may be necessary on your system for the cat command here, depending on your system.)
2. Added fs.file-max = 70000 to /etc/sysctl.conf

ahoward

#! /usr/bin/env ruby

# this script can create a static build from virtually any rails' project.  it
# has two simple requirements.
#
# 1) you have
#
#   gem 'passenger'
#
# in your Gemfile

coreyhaines

Computing
Paul E. Ceruzzi
ISBN: 9780262517676
  
Modeling Business Processes
Wil van der Aalst and Christian Stahl
ISBN: 9780262015387
	
The Reasoned Schemer
Daniel P. Friedman, William E. Byrd, and Oleg Kiselyov

andrewle

Leader Election With Ruby & PostgreSQL

The Problem

I have a table with millions of rows that needs processing. The type of processing is not really important for this article. We simply need to process some data with Ruby --or any other user-space programming language.

A Solution

jbarnette

module Watchable
  def events
    @events ||= Hash.new { |h,k| h[k] = [] }
  end

  def fire event, *args
    events[event].each { |e| e[*args] }
  end

  def on event, &block

ryandotsmith

The Worker Pattern

Contents

• Introduction
• Definition
• Examples
• Links

Introduction