Speeding Ducks Avi Bryant Meta Heckling welcomed. Ruby is slow - - PowerPoint PPT Presentation

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Speeding Ducks Avi Bryant Meta Heckling welcomed. Ruby is slow - - PowerPoint PPT Presentation

Dec 02, 2023 282 likes •628 views

Speeding Ducks Avi Bryant Meta Heckling welcomed. Ruby is slow So what? Of course! So what? The Ruby language may be slow, but my app runs plenty fast True. Ruby ary.pop C VALUE rb_ary_pop(ary) VALUE ary; {

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SLIDE 1

Speeding Ducks

Avi Bryant

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SLIDE 2

Meta

Heckling welcomed.

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SLIDE 3

Ruby is slow

“So what?” “Of course!”

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SLIDE 4

So what?

“The Ruby language may be slow, but my app runs plenty fast”

True.

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SLIDE 5

Ruby

C

VALUE rb_ary_pop(ary) VALUE ary; { rb_ary_modify_check(ary); if (RARRAY(ary)->len == 0) return Qnil; if (!FL_TEST(ary, ELTS_SHARED) &&
  • RARRAY(ary)->len * 2 < RARRAY(ary)->aux.capa &&
  • RARRAY(ary)->aux.capa > ARY_DEFAULT_SIZE) {
  • RARRAY(ary)->aux.capa = RARRAY(ary)->len * 2;
  • REALLOC_N(RARRAY(ary)->ptr, VALUE, RARRAY(ary)->aux.capa);
} return RARRAY(ary)->ptr[--RARRAY(ary)->len]; } ary.pop
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SLIDE 6

Java

ary.pop /** rb_ary_pop * */ public IRubyObject pop() { modify(); if (getLength() == 0) { return getRuntime().getNil(); } return (IRubyObject) list.remove(getLength() - 1); }
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SLIDE 7

Smalltalk

ary.pop
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SLIDE 8

Ruby

C | Java | Smalltalk | ...

def pop() return nil if empty?
  • @total -= 1
index = @start + @total
  • elem = @tuple.at(index)
@tuple.put(index,nil)
  • reallocate_shrink()
  • elem
end
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SLIDE 9 VALUE rb_ary_pop(ary) VALUE ary; { rb_ary_modify_check(ary); if (RARRAY(ary)->len == 0) return Qnil; if (!FL_TEST(ary, ELTS_SHARED) &&
  • RARRAY(ary)->len * 2 < RARRAY(ary)->aux.capa &&
  • RARRAY(ary)->aux.capa > ARY_DEFAULT_SIZE) {
  • RARRAY(ary)->aux.capa = RARRAY(ary)->len * 2;
  • REALLOC_N(RARRAY(ary)->ptr, VALUE, RARRAY(ary)->aux.capa);
} return RARRAY(ary)->ptr[--RARRAY(ary)->len]; }

vs

def pop() return nil if empty?
  • @total -= 1
index = @start + @total
  • elem = @tuple.at(index)
@tuple.put(index,nil)
  • reallocate_shrink()
  • elem
end
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SLIDE 10

Of course!

“Ruby is inherently slow because it is so dynamic.”

False.

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SLIDE 11
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SLIDE 12

Smalltalk-80

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SLIDE 13

Efficient Implentation of the Smalltalk-80 System

  • L. Peter Deutsch

Alan M. Schiffman 1984

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SLIDE 14

Deutsch, 1984 - Native Code

def foo(duck) duck.waddle end mov ... cmp ...

cache

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SLIDE 15

Deutsch, 1984 - Native Code

def foo(duck) duck.quack! end mov ... cmp ...

invalid

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SLIDE 16

Deutsch, 1984 - Inline Caching

def foo(duck) duck.quack! end address = lookup(duck, :quack!) push duck jump(address) def quack! puts “quack” end ...

0xBEEF 0xDECAF

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SLIDE 17

Deutsch, 1984 - Inline Caching

def foo(duck) duck.quack! end def quack! puts “quack” end ...

0xBEEF 0xDECAF

push duck jump(0xBEEF)

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SLIDE 18

Deutsch, 1984 - Inline Caching

def foo(duck) duck.quack! end def quack! puts “quack” end

0xBEEF 0xDECAF

push duck jump(0xBEEF) unless self.class == Duck jump(lookup(self.class, :quack!) end ...

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SLIDE 19

Deutsch, 1984 - Inline Caching

def foo(duck) duck.quack! end def quack! play “q.wav” end

0xBEEF 0xDECAF

push duck jump(0xBEEF) unless self.class == Duck jump(lookup(self.class, :quack!) end ...

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SLIDE 20

Deutsch, 1984 - Inline Caching

def foo(duck) duck.quack! end def quack! puts “quack” end

0xBEEF 0xDECAF

push duck jump(0xBEEF) unless self.class == Duck jump(lookup(self.class, :quack!) end ... address = duck.vtable[3] jump address

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SLIDE 21

SOAR: Smalltalk without Bytecodes

David Ungar Dain Samples Paul Hilfinger 1986

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SLIDE 22

Self

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SLIDE 23

Customization: Optimizing Compiler Technology for Self

David Ungar Craig Chambers 1989

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SLIDE 24

Optimizing Dynamically-Dispatched Calls with Run-Time Type Feedback

David Ungar Urs Hölzle 1994

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SLIDE 25

Self - Polymorphic Inline Caches

def foo(duck) duck.waddle end

Duck: 42 Goose: 7 Doctor: 1

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SLIDE 26

Self - Type feedback inlining

def foo(duck) duck.quack! end def quack! puts “quack” end if duck.class == Duck puts “quack” else ... end

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SLIDE 27

Self - Type feedback inlining

def foo(range) range.collect{|x| x * 2} end def foo(range) result = [] range.each do |x| result.push(x * 2) end result end

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SLIDE 28

Self - Type feedback inlining

def foo(range) range.collect{|x| x * 2} end def foo(range) result = [] i = range.first while(i <= range.last) result.push(i * 2) i += 1 end result end

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SLIDE 29

Self - Type feedback inlining

def foo(range) range.collect{|x| x * 2} end def foo(range) result = [] i = range.first while(i <= range.last) result.push(i << 1) i = i + 1 end result end

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SLIDE 30

Strongtalk

Ungar, Hölzle, Lars Bak, et al

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SLIDE 31

HotSpot

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SLIDE 32
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SLIDE 33
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SLIDE 34

JavaScript