1. Metrics-driven
Engineering at Etsy
MIKE BRITTAIN
mike@etsy.com @mikebrittain

2. Logs, Graphs, Trends,
and Correlations

3. Making Decisions

4. How many visitors are
using this thing?

5. Can we deploy that to
100% of our visitors?

6. Did we make it faster?

7. Did I just break
something?

8. Q. Who makes the graphs?
A. Well, the Ops team manages the network, racks
the servers, installed the monitoring tools, wears
the pagers, blah, blah, blah...

9. (but...) Engineers build
the application.

10. Dev + Ops

11. Access

12. Yes No

13. “Engineers are too busy
meeting our product
deadlines.”

14. Here’s the big secret...

15. Cacti (network, SNMP)
Ganglia (machines)
Graphite (application)
Splunk (log analysis, nightly reports)
Nagios (alerting)

16. Logging

17. Logger::log_error("User login
failed. Reason: $msg for
$username", “login”);

18. web0054 [Fri Mar 04 16:27:48 2011]
[info] [login] User login failed.
Reason: wrong password for ...

19. web0054 [Fri Mar 04 16:27:48 2011]
[info] [login] User login failed.
Reason: wrong password for ...

20. web0054 [Fri Mar 04 16:27:48 2011]
[info] [login] User login failed.
Reason: wrong password for ...

21. web0054 [Fri Mar 04 16:27:48 2011]
[info] [login] User login failed.
Reason: wrong password for ...

22. web0054 [Fri Mar 04 16:27:48 2011]
[info] [login] User login failed.
Reason: wrong password for ...

23. Logster

24. Forked from ganglia-logtailer...
- Daemon mode (only cron mode)
+ Support for Graphite
+ Simplified parsing scripts

25. web0001 [04:28:54 2011] [error] [client 10.101.x.x] Help me, Rhonda.
web0001 [04:28:54 2011] [error] [client 10.101.x.x] Oh noooooo!
web0001 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!
web0001 [04:28:54 2011] [error] [client 10.101.x.x] Heeeeeeellllllllllllllppppp!
web0001 [04:28:54 2011] [error] [client 10.101.x.x] Oh noooooo!
web0001 [04:28:54 2011] [fatal] [client 10.101.x.x] Gaaaaahhh!
web0201 [04:28:54 2011] [warning] [client 10.101.x.x] Gaaaaahhh!
web0034 [04:28:54 2011] [warning] [client 10.101.x.x] Oh nooooooooooo
web0001 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!!!
web1101 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!!!
web0201 [04:28:54 2011] [error] [client 10.101.x.x] You've been eaten by a grue.
web0055 [04:28:54 2011] [fatal] [client 10.101.x.x] Gaaaaahhh!!!
web0002 [04:28:54 2011] [warning] [client 10.101.x.x] Sky is falling.
web0089 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!!!
web0020 [04:28:54 2011] [error] [client 10.101.x.x] Sky is falling.
web1101 [04:28:54 2011] [fatal] [client 10.101.x.x] Gaaaaahhh!
web0055 [04:28:54 2011] [warning] [client 10.101.x.x] Gaaaaahhh!
web0001 [04:28:54 2011] [warning] [client 10.101.x.x] Oh nooooooooooo
web0001 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!!!
web0034 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!!!
web0087 [04:28:54 2011] [fatal] [client 10.101.x.x] Sky is falling.
web0002 [04:28:54 2011] [error] [client 10.101.x.x] Oh noooooo!
web0201 [04:28:54 2011] [fatal] [client 10.101.x.x] Gaaaaahhh!
web0077 [04:28:54 2011] [warning] [client 10.101.x.x] Gaaaaahhh!
web0355 [04:28:54 2011] [warning] [client 10.101.x.x] Oh nooooooooooo
web0052 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!!!
web0001 [04:28:54 2011] [error] [client 10.101.x.x] Gaaaaahhh!!!
web0003 [04:28:54 2011] [error] [client 10.101.x.x] You've been eaten by a grue.
web0066 [04:28:54 2011] [fatal] [client 10.101.x.x] Gaaaaahhh!!!

26. Fatals Errors Warnings

27. StatsD

28. StatsD::increment("logins.success");
StatsD::timing("gearman.time", $msec);

29. 90th pct
average
lower
StatsD::timing("gearman.time", $msec);

30. Ad hoc
name value timestampn

31. echo "events.deploy.site 1 `date +%s`"
| nc graphite.etsycorp.com 2003

32. Trends + Events
target=drawAsInfinite(events.deploy.site)

33. What Happened?

34. 16,000 metrics in Graphite
(plus 32,000 metrics in Ganglia)

35. Dashboards

36. Mix & Match
Dashboards

37. Hard
<a href="http://graphite.etsycorp.com/render?from=-1hours&width=800&height=600&title=File+or
+Script+Not+Found&yMin=0&target=webs.errorLog.notExist&target=drawAsInfinite
%28deploys.config.production%29&target=drawAsInfinite%28deploys.web.production
%29&target=drawAsInfinite%28deploys.search.production%29&target=drawAsInfinite
%28deploys.imagestorage.other%29&colorList=%2300cc00,%230000ff,
%23ff0000,%23006633,%23cc6600">
<img src="http://graphite.etsycorp.com/render?
from=-1hours&width=280&height=220&title=File+or+Script+Not
+Found&hideLegend=1&yMin=0&target=webs.errorLog.notExist&target=drawAsInfinite
%28deploys.config.production%29&target=drawAsInfinite%28deploys.web.production
%29&target=drawAsInfinite%28deploys.search.production%29&target=drawAsInfinite
%28deploys.imagestorage.other%29&colorList=%2300cc00,%230000ff,
%23ff0000,%23006633,%23cc6600">
</a>

38. Easy
$g = new Graphite($time);
$g->setTitle('File Not Found');
$g->addMetric('webs.errorLog.notExist', '#00cc00');
$g->showDeploys(true);
echo $g->getDashboardHTML(280, 220);

39. 20 dashboards by
25 engineers

40. Application health
correlated with events

41. High-level visibility

42. Low MTTD

43. Validation

44. Confidence

45. codeascraft.etsy.com
github.com/etsy/statsd
github.com/etsy/logster
bitbucket.org/maplebed/ganglia-logtailer

46. Q&A
Does this sound like fun? Get in touch with us.
chad@etsy.com kellan@etsy.com
kastner@etsy.com mike@etsy.com