1. Fail Whale

2. Scaling & Rails
You scale a website,
not a framework

3. Scaling SOP's
General Things Standard Operating
Procedures for
website scaling

4. OODA Loop

5. OODA Loop

6. Observe
New Relic
Client (customers) needs
User needs

7. Rumsfeld

8. Rumsfeld
Known knowns
Known unknowns
Unknown unknowns

9. Observe:
Known knowns:
What do we know that we know about
clients?

10. Observe: Known unknowns
Do we know that we know at least a
few pages users are likely to hit
often?

11. Observe: Known unknowns
We know users will use some features
more than others.
We don't know which ones they will
be.

12. Observe: Known unknowns
We know which devices they will be
consuming the site with.
We don't know the percentages for
sure.

13. Observe: Unknown unknowns
What assumptions do we bring, and
which of them may be wrong?

14. Orient
Focus on the known knowns

15. Orient
We know the strategies:

16. Orient
Page Caching
Fragment Caching
Action Caching
Database Caching

17. Decide
Por ejemplo:
To cache the landing page, or
articles, or products
Or
All of the above

18. Act
class ProductsController < ApplicationController
caches_page :index, :show
def index
@products = Product.page(params[:page]).per_page(10)
end
def show
@product = Product.find(params[:id])
end
# Other actions omitted.
end

19. Act
class ProductSweeper < ActionController::Caching::Sweeper
observe Product
def after_update(product)
expire_page products_path
expire_page product_path(product)
expire_page "/"
FileUtils.rm_fr "#{page_cache_directory}/products/page"
end
end

20. Iterate

21. Observe
What do we learn from Httperf
+ Browsermob
+ Apache Bench
+ user feedback?

22. Observe
What have we learned about our
SOP's?

23. Observe
Which known unknowns have become
Known knowns?

24. Observe
Which Unknown unknowns have become
Known unknowns?

25. Orient
Which techniques can be used to
solve the known knowns?

26. Iterate

27. Mise en place

28. [Miz on plas]
Mise en place (pronounced [miz on plas],
literally "putting in place") is a French phrase
defined by the Culinary Institute of America as
"everything in place", as in set up. It is used
in professional kitchens to refer to organizing
and arranging the ingredients (e.g., cuts of
meat, relishes, sauces, par-cooked items,
spices, freshly chopped vegetables, and other
components) that a cook will require for the
menu items that he or she expects to prepare
during his/her shift.[1]

29. GT mise en place
What might our developer kitchen look like?
Our staging kitchen?
Our production kitchen?

30. Development kitchen
Livereload
Rspec
Cucumber
Caching is turned off

31. Development kitchen
Should we turn it on?

32. Development kitchen
Should we turn it on?

33. Development kitchen
HTTPerf & friends:
Allow us to do load testing

34. Development kitchen
Apache bench
$ ab -n 5 -c 5 http://127.0.0.1:3000/articles
-n requests is the number of requests
-c concurrency is the number of multiple requests

35. Development kitchen
HTTPerf
$ brew install httperf
$ httperf --num-conns=20 --rate=10 --timeout=5
--server=localhost --port=3000 --uri=/articles

36. Development kitchen
Autobench:
Allows us to measure load testing
On local machines

37. Development kitchen
Should each developer explicitly
test with caching turned on before
pushing to master?

38. Development kitchen
Or is this inefficient and
confusing?

39. Development kitchen
(Discuss, decide, act, observe,
orient, iterate)

40. Staging Kitchen
CI server runs test suite twice:

41. Staging kitchen
First Jenkins runs with caching off

42. Staging kitchen
Then Jenkins runs with
caching turned on

43. Staging kitchen
Then code gets pushed to staging

44. Staging kitchen
Should features be accepted if they
only pass with caching off?

45. Staging kitchen
If so, we need a second environment,
similar to staging, where caching is
turned on.

46. Staging kitchen
(Discuss, decide, act, observe,
orient, iterate)

47. Production kitchen
What process do we have in place to
get user feedback?

48. Production kitchen
Do we rely on our tools?

49. Production kitchen
How do we get user feedback?

50. Production kitchen
Do we get it from our clients, who
are not our users?

51. Production kitchen
Or do we get it directly (somehow?)

52. To be answered:
1) Do we turn caching on in
development?
2) Do we run tests against caching
before pushing?
3) Do we accept features that
haven't passed caching?

53. Discuss