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I am going M.A.D.
           Monitoring
           Aided
           Development
  From system administration to development and back



FOSDEM11                           Spike Morelli / fsm@spikelab.org
We all code




FOSDEM11             Spike Morelli / fsm@spikelab.org
Monitoring and metrics: a
           lifetime love
  Love for
  monitoring




                                  career




FOSDEM11               Spike Morelli / fsm@spikelab.org
One day in data
           warehousing...

    “There is no such thing as
     too much data, only data
you don't know how to make
             sense of”


FOSDEM11                 Spike Morelli / fsm@spikelab.org
do mind
  information overflow

FOSDEM11       Spike Morelli / fsm@spikelab.org
You, yes you, do you test your code?


FOSDEM11                    Spike Morelli / fsm@spikelab.org
Tests and success rate
           50


           45


           40

                                                                                    TDD
           35


           30


           25                                                                           Num tests
                                                                                        Num pass
           20


           15


           10


            5


           0
                c0   c1   c2   c3   tag-0.1   c5   c6   c7   c8   tag-0.2   c10   c11




FOSDEM11                                                             Spike Morelli / fsm@spikelab.org
What about
           coveragE ?


FOSDEM11            Spike Morelli / fsm@spikelab.org
Tests and COverage
           120




           100




           80




           60                                                                            Num tests
                                                                                         % coverage


           40




           20




            0
                 c0   c1   c2   c3   tag-0.1   c5   c6   c7   c8   tag-0.2   c10   c11




FOSDEM11                                                                 Spike Morelli / fsm@spikelab.org
Lines of code?
   Thanks, but no thanks


FOSDEM11         Spike Morelli / fsm@spikelab.org
LOC, Tests and COverage
            200


            180


            160                                                                           refactoring
            140


            120

                                                                                             Num tests
            100
                                                                                             % coverage
                                                                                             LoC
             80


             60


             40


             20


             0
                  c0   c1   c2   c3   tag-0.1   c5   c6   c7   c8   tag-0.2   c10   c11




FOSDEM11                                                                  Spike Morelli / fsm@spikelab.org
Complexity is your enemy
➠ Callgraph and NESTING
➠ Number and size of functions

➠ Code CLOSURe

➠ Complexity of the build system




FOSDEM11                  Spike Morelli / fsm@spikelab.org
Complexity, Tests, COverage
           50                                                                         120



           45

                                                                                      100
           40


           35
                                                                                      80


           30

                                                                                            Num tests
           25                                                                         60
                                                                                            % coverage
                                                                                            Complexity
           20

                                                                                      40
           15


           10
                                                                                      20


            5


           0                                                                          0
                c0   c1   c2   c3   tag-0.1   c5   c6   c7   c8   tag-0.2 c10   c11




FOSDEM11                                                                   Spike Morelli / fsm@spikelab.org
Do it with style
➠ Lintian
➠ Pep8

➠ Reward beautiful code




FOSDEM11                  Spike Morelli / fsm@spikelab.org
Take a step back, a
            large breath and
                reflect


FOSDEM11                Spike Morelli / fsm@spikelab.org
Do not do what a machine
               can do.
        hello HUDSON Jenkins



FOSDEM11              Spike Morelli / fsm@spikelab.org
Being on-call sucks
                 big TIME




FOSDEM11                 Spike Morelli / fsm@spikelab.org
HOW > IF


      “It is never too early to
           start monitoring your
           application's behaviour”



FOSDEM11                     Spike Morelli / fsm@spikelab.org
Write code that is
           monitoring friendly




FOSDEM11                 Spike Morelli / fsm@spikelab.org
OPS is changing
➠ Configuration management
➠ Infrastructure-as-c0de

➠ Behaviour driven development

   ➠ Cucumber

   ➠ Robotframework

➠ Continuous integration for OPS




FOSDEM11                 Spike Morelli / fsm@spikelab.org
...and you can help
➠   If you are an op
     ➠ Realize and accept that you code

     ➠ There are lots of good reusable

       development patterns
     ➠ Advertise your achievements

     ➠ Engage your developers




FOSDEM11                    Spike Morelli / fsm@spikelab.org
...and you can help
➠   If you are a dev
     ➠ Treat ops as developer, don't exclude

       them
     ➠ Share the knowledge

     ➠ Code applications that are easier to

       monitor
     ➠ Learn from your ops how to make

       your app production ready

FOSDEM11                      Spike Morelli / fsm@spikelab.org
The most important metric




           TRUST
FOSDEM11             Spike Morelli / fsm@spikelab.org
Don't let uncertainty drive
              you insane,
              go M.A.D.


FOSDEM11                  Spike Morelli / fsm@spikelab.org
Thanks everybody
➠ Http://www.spikelab.org
➠ fsm@spikelab.org

➠ @spikelab




FOSDEM11                Spike Morelli / fsm@spikelab.org

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I am going M.A.D - Monitoring Aided Development

  • 1. I am going M.A.D. Monitoring Aided Development From system administration to development and back FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 2. We all code FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 3. Monitoring and metrics: a lifetime love Love for monitoring career FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 4. One day in data warehousing... “There is no such thing as too much data, only data you don't know how to make sense of” FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 5. do mind information overflow FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 6. You, yes you, do you test your code? FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 7. Tests and success rate 50 45 40 TDD 35 30 25 Num tests Num pass 20 15 10 5 0 c0 c1 c2 c3 tag-0.1 c5 c6 c7 c8 tag-0.2 c10 c11 FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 8. What about coveragE ? FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 9. Tests and COverage 120 100 80 60 Num tests % coverage 40 20 0 c0 c1 c2 c3 tag-0.1 c5 c6 c7 c8 tag-0.2 c10 c11 FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 10. Lines of code? Thanks, but no thanks FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 11. LOC, Tests and COverage 200 180 160 refactoring 140 120 Num tests 100 % coverage LoC 80 60 40 20 0 c0 c1 c2 c3 tag-0.1 c5 c6 c7 c8 tag-0.2 c10 c11 FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 12. Complexity is your enemy ➠ Callgraph and NESTING ➠ Number and size of functions ➠ Code CLOSURe ➠ Complexity of the build system FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 13. Complexity, Tests, COverage 50 120 45 100 40 35 80 30 Num tests 25 60 % coverage Complexity 20 40 15 10 20 5 0 0 c0 c1 c2 c3 tag-0.1 c5 c6 c7 c8 tag-0.2 c10 c11 FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 14. Do it with style ➠ Lintian ➠ Pep8 ➠ Reward beautiful code FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 15. Take a step back, a large breath and reflect FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 16. Do not do what a machine can do. hello HUDSON Jenkins FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 17. Being on-call sucks big TIME FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 18. HOW > IF “It is never too early to start monitoring your application's behaviour” FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 19. Write code that is monitoring friendly FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 20. OPS is changing ➠ Configuration management ➠ Infrastructure-as-c0de ➠ Behaviour driven development ➠ Cucumber ➠ Robotframework ➠ Continuous integration for OPS FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 21. ...and you can help ➠ If you are an op ➠ Realize and accept that you code ➠ There are lots of good reusable development patterns ➠ Advertise your achievements ➠ Engage your developers FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 22. ...and you can help ➠ If you are a dev ➠ Treat ops as developer, don't exclude them ➠ Share the knowledge ➠ Code applications that are easier to monitor ➠ Learn from your ops how to make your app production ready FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 23. The most important metric TRUST FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 24. Don't let uncertainty drive you insane, go M.A.D. FOSDEM11 Spike Morelli / fsm@spikelab.org
  • 25. Thanks everybody ➠ Http://www.spikelab.org ➠ fsm@spikelab.org ➠ @spikelab FOSDEM11 Spike Morelli / fsm@spikelab.org

Notes de l'éditeur

  1. Wanna share my experience What I learned going dev and what I brought back SHOW OF HANDS, how many admins, how many devs? How many that do both? Do we have QA?
  2. * Start by saying strongly believe into: everybody codes * As a sysadmin start lots oneliners * Not enough bash scripts * More complex, perl python ruby scripts * Still doesn't feel like coding * You're looked upon as a non dev * But was “hello world” coding? Why? * Yes maybe not a great dev, but still * This is bad, creates wrong culture * You can test bash scripts * Also another important stepping stone: infrastructure as code. * Puppet manifests * what about QA? Test scripts and automation, isn't that code? * So you see, we all code
  3. * Loved monitoring since day one * Simple idea of knowing nagios was checking stuff for me made me sleep better * Then discovered metrics, world of wonders. * A complete change of perspective, not only you know if something is broken, but you know how it's doing * How am I supposed to answer any question on the state of my systems? * think of it as if we you were a doctor. * western doctors Vs chinese doctors * Anecdotal chinese doctor , you didn't pay when you were sick . No longer true unfortunately
  4. * I was on loan to dw for a few months * that's where my passion for data and viz was born * met a fellow data monger that was amazing, he could dig out of piles of data the most amazing things and he was usually right. * the all process was like magic, like looking at the matrix encrypted and see'ing people * the guy could look at a pile of data and see patterns, questions and answers – next * before sounding completely nuts about metrics
  5. * can be mislead * miss things in the noise * requires more effort to make sense of things * there are no free lunches. But the benefit can be huge
  6. * didnt use test, too hard, no understand, felt no dev * worked in the right place, was exposed to tests, it INSPIRED ME * still no tests cuz team was SE, me complacent * When startup making a product, I've got no excuse, especially being alone with no QA. * Bugs will make you lose customers * started with unittesting, then tdd * realized was doing TDD with nagios, check deployed before srv and then pass service was live * Testing upfront was awesome, confidence went up * Use TDD to do security * New metrics! Add tests, success rate, monitor my progress
  7. * says something at a glance * was sloppy testing * until I wanted to release * and I diverged again afterwards * so I started to do tdd I didn't diverge anymore * would have I been able to notice without this graph? * the graph empowered me to spot a behaviour * what's the benefit? You know, you can prove the effectiveness, – next * but then you wonder, how much code am I testing?
  8. * Adding tests alone is not meaningful * You wonder about them * In Nagios you did the same, you test a port, but what does that cover? * More and more people do end-to-end checks
  9. * again, you can notice something at a glance * adding tests does not mean adding coverage * also see for 0.2 I hit 100% but I've only added a few tests? * let's see next slide
  10. * you gotta start somewhere * that somewhere is usually wrong :) * nonetheless, I found 'em useful for something == Next slide * remember from the previous slide that I hit 100% without adding many tests?
  11. * once again metrics tell us something we'd otherwise missed * tell us why we achieved 100% == Next * but loc is a poor metric after all * more or less lines of code aren't that important * what matters is complexity!
  12. * complexity is your enemy * KISS * calculating complexity is a huge thing, you could make a talk on it * no secret formula, I just got the idea from spamming systems to use scoring * so what are interesting metrics about complexity? * ask audience, can anybody think of another? http://michaelfeathers.typepad.com/michael_feathers_blog/2011/01/measuring-the-closure-of-code.html
  13. * once again metrics tell us a story * stories are far more powerful than numbers
  14. * style matters * good code is more readable * easier to understand and refactor * less prone to contain bugs * it makes you feel better
  15. * discussed lots of metrics * wanted to make a point they should help you, not hinder you * people say “create a metric and people will game it” * lots of books on psychology make a scary point about rewards * by any mean toss them if they hurt you * remind yourself about the peril * with great powers, come great responsibility. So it does with metrics.
  16. * quite simple really * moved it into a CI * buildbot would work too – Next slide * all excited by these metrics and developing that I forgot where I came from
  17. * that's where I come from * how many people here have actually been on-call before? * Hard to appreciate if you've never been on-call in an ops team. * Had been a sysadmin for a while, but not oncall and it was a shock * After I left every time I was in a public places and someone had the same ringtone I twitched * SO WHAT CAN YOU DO?
  18. * how long do your unit tests take? * has this changed? * how much cpu or mem during the last global pass? * do you build your sw? How long does that take? Has that changed? * Do you run integration tests? That's like live, monitor those systems! * cheap way to profile your app * Very useful and possible to spot mem leak or cpu increase
  19. If it's never too early to start monitoring your app, never too early yo make your app easy to monitor We're making good progress, think memcached mgmt interface, mysql session variables MAKE COLLECTION EASY SOME EXAMPLES: HTTP REQUEST TIMING SIZE OF REQUEST DB QUERY TIME NUMBER OF CONNECTED CLIENTS TOP REQUESTS
  20. * CM been a long time resident (cfengine) * but now many more people do it (still lots to do tho) * infra-as-code is a result of CM. Name says it all * Consulting for a company now that uses jenkins and we're building one in ops to do CI for scripts and puppet manifests * as we move toward this direction need more access to devs to be successful
  21. * use a vcs * branch * test
  22. * anybody wants to guess? * trust in your code ** that's why you test, test your code works, trust you can change it * trust in the people ** stealing from patric debois ** trust tax * at the end of the day you don't want to test for fun * test for profit, to make a good job * you can't make a good job without trusting yourself and the people that work with you * especially true across departments (Dev/ops) * I BELIEVE THAT TESTING CAN BE THE PLATFORM TO BUILD TRUST UPON AND FOSTER THE CULTURAL CHANGE THAT DEVOPS IS ALL ABOUT