I gave this talk at Lone Star Ruby Conference in Austin on 8/28/2010.

1. A Scalable Rails app
Deployed in 60
seconds
1

2. Ben Scheirman
• Director of Development at ChaiONE
• Microsoft MVP, ASP Insider
• Certified ScrumMaster
• Former .NET Ninja, now Rails/iPhone
aficionado
2

3. Ben Scheirman
• ...not affiliated with Heroku
3

4. So you have a fantastic app?
4

5. 5

6. 6

7. 7

8. 7

9. 7

10. 7

11. 7

12. 7

13. 8

14. 8

15. 9

16. 10

17. 11

18. x 1,000?
11

19. 12

20. x 10,000?
12

21. writes
reads
13

22. writes
reads
x 1,000,000?
13

23. 14

24. On-Demand
15

25. # Users by time of day
400
300
200
100
0
12 AM 3AM 6AM 9AM 12PM 3PM 6PM 9PM 12AM
16

26. # Users by time of day
400
300
200
100
0
12 AM 3AM 6AM 9AM 12PM 3PM 6PM 9PM 12AM
16

27. # Users by time of day
400
300
200
100
0
12 AM 3AM 6AM 9AM 12PM 3PM 6PM 9PM 12AM
Only need massive scale from 9am - 9pm
16

28. Expected Users For PR Campaign
900
675
450
225
0
Mar 1 Mar 15 Apr 1 Apr 15 May 1 May 15 Jun 1 Jun 2
17

29. Expected Users For PR Campaign
900
675
450
225
0
Mar 1 Mar 15 Apr 1 Apr 15 May 1 May 15 Jun 1 Jun 2
17

30. SCALE
18

31. 19

32. Awesome Shredder Art by Dan Barret
20

33. gem install heroku
Awesome Shredder Art by Dan Barret
20

34. • Platform as a service for Rack-based apps
• Scale easily
• Great workflow
• Free to start / Friendly Pricing
• Complete command-line API
21

35. Deploy a rails app in 5 steps
git init
git add .
git commit -m “My First Commit”
heroku create
git push heroku master
Creating morning-summer-18..... done
Created http://morning-summer-18.heroku.com/ | git@heroku.com:morning-summer-18.git
22

36. Deploy a rails app in 5 steps
git init
git add .
git commit -m “My First Commit”
heroku create
git push heroku master
Creating morning-summer-18..... done
Created http://morning-summer-18.heroku.com/ | git@heroku.com:morning-summer-18.git
LET THAT SOAK IN...
22

37. Using git for deployment is f***ing
GENIUS
23

38. Technology
• Amazon Web Services
• Caching w/ Varnish
• Debian Linux
• Erlang Routing Mesh
• Nginx
• PostgreSQL
24

39. 25

40. How Heroku Scales
26

41. How Heroku Scales
or WTF is a Dyno?
26

42. How Heroku Scales
or WTF is a Dyno?
26

43. How Heroku Scales
or WTF is a Dyno?
26

44. How Heroku Scales
27

45. How Heroku Scales
27

46. How Heroku Scales
27

47. When to add dynos
• Increasing response times
• “Backlog Too Deep” Error
28

48. Always Measure
• New Relic RPM
• Apache Bench
29

49. Heroku Tips
• Multiple Heroku apps for Test, Staging,
Production
• Learn the awesome-ness of Taps
• Heroku logs
• Heroku Console
• Useful addons: New Relic, Exceptional
30

50. Backups
31

51. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
32

52. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
33

53. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
34

54. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
35

55. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
36

56. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
37

57. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
38

58. Coping with the Free Single Bundle
task :backup do
bundle_name = "my-backup"
heroku_app = ENV['app']
def wait_for_response_text(text)
heroku_app = ENV['app'] #lame, I know
begin
puts "."
bundles = `heroku bundles --app #{heroku_app}`
end while bundles.match(text).nil?
end
#check for existing bundle
bundles = `heroku bundles --app #{heroku_app}`
unless bundles.match /has no bundles/
`heroku bundles:destroy #{bundle_name} --app #{heroku_app}`
wait_for_response_text 'has no bundles'
end
puts "Capture bundle #{bundle_name}..."
`heroku bundles:capture #{bundle_name} --app #{heroku_app}`
wait_for_response_text "complete"
puts "Downloading bundle..."
`heroku bundles:download #{bundle_name} --app #{heroku_app}`
timestamp = `date -u '+%Y-%m-%d-%H-%M'`.chomp
new_path = "backups/#{heroku_app}-#{timestamp}.tar.gz"
mkdir "backups" unless File.exists? "backups"
`mv #{heroku_app}.tar.gz #{new_path}`
puts "Bundle saved to #{new_path}" end
end
39

59. One-button Deployments
task :deploy do
heroku_app = ENV['app']
heroku_config = Hash.new
Rake::Task["heroku:backup"].invoke
puts "Turning maintenance on..."
puts "** " + `heroku maintenance:on --app #{heroku_app}`
sleep 15 #maintenance mode causes your slug to be recompiled
puts "Pushing changes to heroku..."
puts "** " + `git push #{git_remotes[heroku_app]} master`
puts "Migrating heroku databases..."
puts "** " + `heroku rake db:migrate --app #{heroku_app}`
puts "Setting up config variables..."
heroku_config.each_pair do |k, v|
puts "** " + `heroku config:add #{k.to_s.upcase}=#{v}`
end
puts "Turning maintenance mode off"
puts "** " + `heroku maintenance:off --app #{heroku_app}`
puts "DEPLOYMENT DONE!"
end
40

60. Delayed Jobs
41

61. Delayed Jobs
def send_bulk_emails
BulkEmailSender.send_a_ton
flash[:notice] => "Ok we sent them"
end
41

62. Delayed Jobs
def send_bulk_emails
BulkEmailSender.send_a_ton
flash[:notice] => "Ok we sent them"
end
def send_bulk_emails
BulkEmailSender.send_later(:send_a_ton)
flash[:notice] => "Ok we sent them"
end
41

63. Delayed Jobs
42

64. Delayed Jobs
> gem install delayed_job
> rails g delayed_job
> rake db:migrate
42

65. Delayed Jobs
> gem install delayed_job
> rails g delayed_job
> rake db:migrate
> heroku workers 1
simple-snow-68 now running 1 worker
> heroku workers +1
simple-snow-68 now running 2 workers
42

66. Delayed Jobs
43

67. Delayed Jobs
$0.05 per hour / worker
(even when it's not processing Jobs)
43

68. Delayed Jobs
$0.05 per hour / worker
(even when it's not processing Jobs)
http://github.com/pedro/delayed_job/commit/
09d7657e1fc7d25072e6c5e73ede20d6e1185eac
http://bit.ly/9Qokff
43

69. Delayed Jobs
Pedro's Fork / auto-scale branch
44

70. Delayed Jobs
Pedro's Fork / auto-scale branch
//lib/delayed/job.rb
def after_create
Manager.scale_up if self.class.auto_scale &&
Manager.qty == 0
end
//lib/delayed/worker.rb
Manager.scale_down if count.zero? &&
Job.auto_scale &&
Job.count == 0
44

71. • Read-only file system
• some gems don’t work
• File uploads?
• Temp Directory
• SSL, memcached, Full-text-search expensive
• Bound-by Amazon’s SLA
45

72. contact = {
! :blog => http://flux88.com,
!
! :twitter => @subdigital,
!
! :email => ben@scheirman.com
}
46

73. 47