Introduction to OpenTuner

78 Pages·2015·2.05 MB·English

by  Jason Ansel

Today’s Agenda
(cid:73) 08:30 Welcome and broader context (Saman Amarasinghe)
(cid:73) 08:40 Introduction to OpenTuner (Jason Ansel)
(cid:73) 09:10 Search techniques (Kalyan Veeramachaneni)
(cid:73) 09:35 In depth example (Jeffrey Bosboom)
(cid:73) 10:00 Break
(cid:73) 10:15 Applications
(cid:73) Halide (Jonathan Ragan-Kelley)
(cid:73) SEJITS (Chick Markley)
(cid:73) JVM optimization (Tharindu Rusira)
(cid:73) 11:00 Hands on session (Shoaib Kamil)
(cid:73) 11:45 Discussion
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Introduction to OpenTuner
Jason Ansel
MIT-CSAIL
Febuary 8, 2015
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$ g++−O3−o raytracer a raytracer.cpp
$ time ./raytracer a
./raytracer a 0.17s user 0.00s system 99% cpu 0.175 total
1.47x speedup with:
$ g++−O3−o raytracer b apps/raytracer.cpp −funsafe−math−optimizations −fwrapv
(cid:44)→−fno−expensive−optimizations −−param=max−peel−branches=115−fweb −fno−
(cid:44)→ cx−fortran−rules −−param=max−inline−recursive−depth=25−fno−btr−bb−
(cid:44)→ exclusive −fno−tree−ch−−param=iv−max−considered−uses=69−fgcse−las −
(cid:44)→ ftree−loop−distribution −−param=max−goto−duplication−insns=11−−param=
(cid:44)→ max−hoist−depth=44−fsched−stalled−insns−dep−−param=max−once−peeled−
(cid:44)→ insns=165−−param=max−pipeline−region−insns=316−−param=iv−consider−all
(cid:44)→−candidates−bound=75
$ time ./raytracer b
./raytracer b 0.12s user 0.00s system 99% cpu 0.119 total
Raytracer Example
An example ray tracer program: raytracer.cpp
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1.47x speedup with:
$ g++−O3−o raytracer b apps/raytracer.cpp −funsafe−math−optimizations −fwrapv
(cid:44)→−fno−expensive−optimizations −−param=max−peel−branches=115−fweb −fno−
(cid:44)→ cx−fortran−rules −−param=max−inline−recursive−depth=25−fno−btr−bb−
(cid:44)→ exclusive −fno−tree−ch−−param=iv−max−considered−uses=69−fgcse−las −
(cid:44)→ ftree−loop−distribution −−param=max−goto−duplication−insns=11−−param=
(cid:44)→ max−hoist−depth=44−fsched−stalled−insns−dep−−param=max−once−peeled−
(cid:44)→ insns=165−−param=max−pipeline−region−insns=316−−param=iv−consider−all
(cid:44)→−candidates−bound=75
$ time ./raytracer b
./raytracer b 0.12s user 0.00s system 99% cpu 0.119 total
Raytracer Example
An example ray tracer program: raytracer.cpp
$ g++−O3−o raytracer a raytracer.cpp
$ time ./raytracer a
./raytracer a 0.17s user 0.00s system 99% cpu 0.175 total
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Raytracer Example
An example ray tracer program: raytracer.cpp
$ g++−O3−o raytracer a raytracer.cpp
$ time ./raytracer a
./raytracer a 0.17s user 0.00s system 99% cpu 0.175 total
1.47x speedup with:
$ g++−O3−o raytracer b apps/raytracer.cpp −funsafe−math−optimizations −fwrapv
(cid:44)→−fno−expensive−optimizations −−param=max−peel−branches=115−fweb −fno−
(cid:44)→ cx−fortran−rules −−param=max−inline−recursive−depth=25−fno−btr−bb−
(cid:44)→ exclusive −fno−tree−ch−−param=iv−max−considered−uses=69−fgcse−las −
(cid:44)→ ftree−loop−distribution −−param=max−goto−duplication−insns=11−−param=
(cid:44)→ max−hoist−depth=44−fsched−stalled−insns−dep−−param=max−once−peeled−
(cid:44)→ insns=165−−param=max−pipeline−region−insns=316−−param=iv−consider−all
(cid:44)→−candidates−bound=75
$ time ./raytracer b
./raytracer b 0.12s user 0.00s system 99% cpu 0.119 total
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(cid:73) Specific to:
(cid:73) raytracer.cpp
(cid:73) Same flags are 1.42x slower than -O1 for fft.c
(cid:73) GCC 4.8.2-19ubuntu1
(cid:73) Intel Core i7-4770S
(cid:73) Autotuners can help!
iv-consider-all-candidates-bound what???
This command is brittle and confusing:
$ g++−O3−o raytracer b apps/raytracer.cpp −funsafe−math−optimizations −fwrapv
(cid:44)→−fno−expensive−optimizations −−param=max−peel−branches=115−fweb −fno−
(cid:44)→ cx−fortran−rules −−param=max−inline−recursive−depth=25−fno−btr−bb−
(cid:44)→ exclusive −fno−tree−ch−−param=iv−max−considered−uses=69−fgcse−las −
(cid:44)→ ftree−loop−distribution −−param=max−goto−duplication−insns=11−−param=
(cid:44)→ max−hoist−depth=44−fsched−stalled−insns−dep−−param=max−once−peeled−
(cid:44)→ insns=165−−param=max−pipeline−region−insns=316−−param=iv−consider−all
(cid:44)→−candidates−bound=75
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(cid:73) Autotuners can help!
iv-consider-all-candidates-bound what???
This command is brittle and confusing:
$ g++−O3−o raytracer b apps/raytracer.cpp −funsafe−math−optimizations −fwrapv
(cid:44)→−fno−expensive−optimizations −−param=max−peel−branches=115−fweb −fno−
(cid:44)→ cx−fortran−rules −−param=max−inline−recursive−depth=25−fno−btr−bb−
(cid:44)→ exclusive −fno−tree−ch−−param=iv−max−considered−uses=69−fgcse−las −
(cid:44)→ ftree−loop−distribution −−param=max−goto−duplication−insns=11−−param=
(cid:44)→ max−hoist−depth=44−fsched−stalled−insns−dep−−param=max−once−peeled−
(cid:44)→ insns=165−−param=max−pipeline−region−insns=316−−param=iv−consider−all
(cid:44)→−candidates−bound=75
(cid:73) Specific to:
(cid:73) raytracer.cpp
(cid:73) Same flags are 1.42x slower than -O1 for fft.c
(cid:73) GCC 4.8.2-19ubuntu1
(cid:73) Intel Core i7-4770S
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iv-consider-all-candidates-bound what???
This command is brittle and confusing:
$ g++−O3−o raytracer b apps/raytracer.cpp −funsafe−math−optimizations −fwrapv
(cid:44)→−fno−expensive−optimizations −−param=max−peel−branches=115−fweb −fno−
(cid:44)→ cx−fortran−rules −−param=max−inline−recursive−depth=25−fno−btr−bb−
(cid:44)→ exclusive −fno−tree−ch−−param=iv−max−considered−uses=69−fgcse−las −
(cid:44)→ ftree−loop−distribution −−param=max−goto−duplication−insns=11−−param=
(cid:44)→ max−hoist−depth=44−fsched−stalled−insns−dep−−param=max−once−peeled−
(cid:44)→ insns=165−−param=max−pipeline−region−insns=316−−param=iv−consider−all
(cid:44)→−candidates−bound=75
(cid:73) Specific to:
(cid:73) raytracer.cpp
(cid:73) Same flags are 1.42x slower than -O1 for fft.c
(cid:73) GCC 4.8.2-19ubuntu1
(cid:73) Intel Core i7-4770S
(cid:73) Autotuners can help!
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How to Autotune a Program
Program
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How to Autotune a Program
Program
Search Space
Definition
Executes
Run Method
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