Share
Embed
Slide 1
Slide 1 text
Elixir を⽀える技術 -「落ちない」システムの秘密に迫る
Elixir: Under the Hood
Takanori Ishikawa / builderscon tokyo 2019
Slide 2
Slide 2 text
Copyright © ABEJA, Inc. All rights reserved.
Elixir: Under the Hood
Elixir を⽀える技術 -「落ちない」システムの秘密に迫る
Slide 3
Slide 3 text
Copyright © ABEJA, Inc. All rights reserved.
• @takanori_is
• Takanori Ishikawa
• ABEJA, inc.
• Ex) mixi, Drecom
• Developer in ABEJA Platform
• ❤ Elixir and
• https://github.com/ishikawa
• Born in 愛媛県松⼭市
Slide 4
Slide 4 text
Copyright © ABEJA, Inc. All rights reserved.
Summary
• Erlang & Elixir design and principal
• Systems that run forever
• BEAM internal
• Optimizations for BEAM
Slide 5
Slide 5 text
Copyright © ABEJA, Inc. All rights reserved.
Erlang
Slide 6
Slide 6 text
Copyright © ABEJA, Inc. All rights reserved.
History of Erlang
• 1982 - 1985: Experiments using > 20 different languages
• 1985 - 86: Experiments with Lisp,Prolog, Parlog
• 1987: Erlang
• 1993: Distribution
• 1998: Open Sourced
Slide 7
Slide 7 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 8
Slide 8 text
Copyright © ABEJA, Inc. All rights reserved. https://medium.com/elixirlabs/anatomy-of-an-elixir-process-878030c37166
Slide 9
Slide 9 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 10
Slide 10 text
Copyright © ABEJA, Inc. All rights reserved.
Elixir
Slide 11
Slide 11 text
Copyright © ABEJA, Inc. All rights reserved.
Elixir Design Goals
• Compatibility
• the Erlang VM is Elixir’s strongest asset
• Productivity
• Extensibility
Slide 12
Slide 12 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 13
Slide 13 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 14
Slide 14 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 15
Slide 15 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 16
Slide 16 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 17
Slide 17 text
Copyright © ABEJA, Inc. All rights reserved. https://blog.stenmans.org/theBeamBook/#ERTS
Slide 18
Slide 18 text
Copyright © ABEJA, Inc. All rights reserved.
「落ちないシステム」
Slide 19
Slide 19 text
Copyright © ABEJA, Inc. All rights reserved.
「100% バグがないシステムを
作れば落ちない！」
Slide 20
Slide 20 text
Copyright © ABEJA, Inc. All rights reserved.
Systems run forever
• Process Isolation
• Fault tolerance
• Self healing
Slide 21
Slide 21 text
Copyright © ABEJA, Inc. All rights reserved.
The Erlang Virtual Machine:
BEAM
Slide 22
Slide 22 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 23
Slide 23 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 24
Slide 24 text
Copyright © ABEJA, Inc. All rights reserved.
The Erlang Virtual Machine: BEAM
• BEAM (Bogumil’s/Björn’s Abstract Machine)
• garbage collecting
• reduction counting
• non-preemptive
• Interpreter loop: directly threaded
• register machine
Slide 25
Slide 25 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 26
Slide 26 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 27
Slide 27 text
Copyright © ABEJA, Inc. All rights reserved.
Process
• Heap
• Stack
• Mailbox
• PCB (Process Control Block)
Slide 28
Slide 28 text
Copyright © ABEJA, Inc. All rights reserved.
https://hamidreza-s.github.io/erlang/scheduling/real-time/preemptive/migration/2016/02/09/erlang-scheduler-
details.html
Erlang VM
+--------------------------------------------------------+
| |
| +-----------------+-----------------+ |
| | | | |
| | Scheduler # 1 | Run Queue # 1 <--+ |
| | | | | |
| +-----------------+-----------------+ | |
| | |
| +-----------------+-----------------+ | |
| | | | | |
| | Scheduler # 2 | Run Queue # 2 <----> Migration |
| | | | | Logic |
| +-----------------+-----------------+ | |
| | |
| +-----------------+-----------------+ | |
| | | | | |
| | Scheduler # N | Run Queue # N <--+ |
| | | | |
| +-----------------+-----------------+ |
| |
+--------------------------------------------------------+
Slide 29
Slide 29 text
Copyright © ABEJA, Inc. All rights reserved. https://www.erlang-solutions.com/blog/erlang-garbage-collector.html
Slide 30
Slide 30 text
Copyright © ABEJA, Inc. All rights reserved.
Optimization
Slide 31
Slide 31 text
Copyright © ABEJA, Inc. All rights reserved.
HiPE
• High Performance Erlang
• Native code compiler for Erlang
• Including LLVM backend
• Compiles individual Erlang functions
Slide 32
Slide 32 text
Copyright © ABEJA, Inc. All rights reserved.
BEAMJIT
• Since 2014
• Tracing JIT
• LLVM backend
• Future:
• BEAM registers to machine registers
• Cross trace optimizations
Slide 33
Slide 33 text
Copyright © ABEJA, Inc. All rights reserved.
BEAM improvements
• Interpreter Overhaul
• Instruction size reduced
• New IR: SSA based
Slide 34
Slide 34 text
Copyright © ABEJA, Inc. All rights reserved.
SSA
• SSA (Static Single Assignment)
• Each variable is assigned exactly once,
• and every variable is defined before it is used.
• @variable:5
• Simplifies compiler optimizations
Slide 35
Slide 35 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 36
Slide 36 text
Copyright © ABEJA, Inc. All rights reserved.
Slide 37
Slide 37 text
Copyright © ABEJA, Inc. All rights reserved.
Conclusion
Slide 38
Slide 38 text
Copyright © ABEJA, Inc. All rights reserved.
Summary
• Erlang & Elixir design and principal
• Systems that run forever
• BEAM internal
• Optimizations for BEAM
Slide 39
Slide 39 text
Copyright © ABEJA, Inc. All rights reserved.
Thanks!