Build impossible programs

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build impossible programs JULIA EVANS bork

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about a program I built that I wasn't sure would work rb spy

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I 800 debugging profiling tools

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ftp.sina.io yYIato OEht

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GOAL 12016 Write a profiler that will work with and running Ruby program

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Ei O myipn f

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what I knew profilers like this existed for C Java 997 Your kite to perf as

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why doesn t go.othaisreaefjs.fm ftp.iismptohsissible uT

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myths about doing innovative work i i

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myths you have to be an expert if it were possible worthwhile somebody would have done it you have to code on the weekend

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MYTH ti

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some minor problems understanding of Ruby internals none Ruby OSS contributions none profilers 1debuggers written O it trust 1C skills beginner

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alternative to being an expert find a starting point spend time learning build a prototype

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HE 2016 HE E Q

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Bok 2016 Bok i O

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HE 2016K Recurse center never graduate week f Iprwo pied

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ruby current thread Rstring cfp l seq black panther body location label rb.threao.trb.co roi.frame.trb iseg.t a ct ise µµ µ

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1 week later 5Ucctssu extremely sketchy Rust demo

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No content

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ET i 0 spoiler I didn't work on it for more than a year

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my prototype had serious problems depended on highly unstable details about Ruby interpreter internals 2 3.2 2 3 3 required debugging symbols

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MYTH E

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3 months later Rust conf ei

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make that i o yehud Katz

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REALITY not many people work on Ruby profilers same is true for MANY other I

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MYTH OEI xaoi.neieo.fi praa time

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where am I going to find 400 hours

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where I found the time prototype kzo 6 L week of vacation the rest 2018 3 months paid or

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cold

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o Q

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I have 3 months now what

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TACTICS choose Rust survey the space amazing testing invest in usability document

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on choosing Rust a even though I didn't know it well

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Rost lets me to write fast programs to work with C data structures to write programs with no faults memory leaks

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g for ambitious projects you might need new tools

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TACTIC survey prior art

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goal find out how every Ruby Python profiler works doing this took 1 day

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3 kinds of profilers to tracing profilers same process to sampling profilers same process to pyflame

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how to find struct layouts pyflame compile time header files my demo runtime DWARF

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how to find struct layouts pyflame compile time header files rbspy runtime compile time

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TACTIC invest in testing

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rb spy testing strategy collect core dumps memory snapshots for 5 6 different Ruby versions of test on those

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result only 1 bug report about incompatibility with Ruby binary reported in 2 months

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TACTIC invest in usability

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features nobody can use might as well not exist

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how flame graphs usually work to git clone github.com I add it to your PATH to cat data 1 flame graph.pl

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how flame graphs work in rbspy run rbspy record rbspy automatically creates a flame graph

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I qq.EU jcheerfulstoiccommented23daYJ I'm not sure if flame graphs are available in other tools but the ease and accessibility of them in rbspv brought them to me for the first time t

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write documentation

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rbspy.github.io

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I spent 400 hours on this project

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it mostly works I E.EE andrewhamptoncommented on Mar 30 I do a lot of work on a rails appthat's over 70yearsold I used rbspy record bundle exec rspec ftp aefeweeshagnniortoprmaesef.tv configuredthe script The CPUtime for the entire suitedroppedbynearlyan hour Thanks junsfor theamazingtool

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give yourself the time to do something 0 ambitious as

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qinermeonisso oasis toot 2017 2018 julia julia

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provide sabbaticals thanks stripe Fund open source thanks

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g yan bcrypt A lot of people ask why should I work in software development as opposed to math physicsHinanceletc One reason is that this field is surprisingly full of inadequate equilibria a steady state in which low hanging fruits are still available for non experts to solve 20 11428 07,487

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go build something impossible