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https://research.swtch.com/interfaces](https://image.slidesharecdn.com/gofast-170929191746/75/So-You-Wanna-Go-Fast-50-2048.jpg)
![@tyler_treat
tab
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s := Stringer(b)
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https://research.swtch.com/interfaces](https://image.slidesharecdn.com/gofast-170929191746/75/So-You-Wanna-Go-Fast-51-2048.jpg)
![@tyler_treat
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Uploaded byTyler Treat
So You Wanna Go Fast?
This document contains the transcript from a presentation titled "So You Wanna Go Fast?" by Tyler Treat. Some of the key topics discussed include measuring performance using tools like pprof, how different language features in Go like channels, interfaces, and memory management can impact performance, and techniques for writing concurrent and multi-core friendly code in Go like using read-write mutexes. The overall message is that performance depends greatly on the specific situation and trade-offs must be considered between concurrency, memory usage, and execution speed. Measuring first is emphasized to guide any optimizations.
More Related Content
So You Wanna Go Fast?
- 1. Wanna Go So You Fast? StrangeLoop 2017 @tyler_treat
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- 3. @tyler_treat this one weirdtrick Make your code faster with
- 4. @tyler_treat this one weirdtrick Make your code faster with
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- 6. @tyler_treat Spoiler Alert: Go isnot a systems language…
- 7. @tyler_treat but that doesn’tmean you can’t build internet-scale systems with it.
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- 9. @tyler_treat This is atalk about how to write terrible Go code.
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- 11. @tyler_treat Because this isa talk about trade-offs.
- 12. @tyler_treat - Messaging Nerd@ Apcera - Working on nats.io - Distributed systems - bravenewgeek.com Tyler Treat
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- 17. @tyler_treat You have tobe mindful of performance when it matters.
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- 19. @tyler_treat@tyler_treat Where bad thingshideWhere we’re usually looking
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- 24. @tyler_treat Overview - Measuring performance -Language features - Memory management - Concurrency and multi-core
- 25. @tyler_treat Overview - Measuring performance -Language features - Memory management - Concurrency and multi-core
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- 27. @tyler_treat tl;dr of thistalk is “IT DEPENDS!”
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- 29. @tyler_treat Measurement Techniques - pprof -memory - cpu - blocking - GODEBUG - gctrace - schedtrace - allocfreetrace - Benchmarking - Code-level: testing.B - System-level: HdrHistogram (https://github.com/codahale/hdrhistogram) bench (https://github.com/tylertreat/bench)
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- 31. @tyler_treat The only wayto get good at something is to be really fucking bad at it for a long time.
- 32. @tyler_treat Benchmarking… a great wayto rattle the Hacker News fart chamber.
- 33. @tyler_treat Overview - Measuring performance -Language features - Memory management - Concurrency and multi-core
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- 35. @tyler_treat “Instead of explicitlyusing locks to mediate access to shared data, Go encourages the use of channels to pass references to data between goroutines.” https://blog.golang.org/share-memory-by-communicating
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- 37. @tyler_treat@tyler_treat USE CHANNELS TOCOORDINATE, NOT SYNCHRONIZE.
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- 44. @tyler_treat The Secret Life ofinterface{}
- 45. @tyler_treat type Stringer interface{ String() string } https://research.swtch.com/interfaces
- 46. @tyler_treat type Stringer interface{ String() string } type Binary uint64 https://research.swtch.com/interfaces
- 47. @tyler_treat type Stringer interface{ String() string } type Binary uint64 200 b := Binary(200) https://research.swtch.com/interfaces
- 48. @tyler_treat type Stringer interface{ String() string } type Binary uint64 func (i Binary) String() string { return strconv.FormatUint(uint64(i), 2) } 200 b := Binary(200) https://research.swtch.com/interfaces
- 49. @tyler_treat type Stringer interface{ String() string } https://research.swtch.com/interfaces s := Stringer(b) Stringer tab data
- 50. @tyler_treat s := Stringer(b) Stringer tab data . . . itable(Stringer,Binary) type fun[0] type(Binary) (*Binary).String type Stringer interface { String() string } https://research.swtch.com/interfaces
- 51. @tyler_treat tab data 200 Binary s := Stringer(b) Stringer . . . itable(Stringer,Binary) type fun[0] type(Binary) (*Binary).String type Stringer interface { String() string } https://research.swtch.com/interfaces
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- 60. @tyler_treat $ go test-bench=. -gcflags="-m"
- 61. @tyler_treat $ go test-bench=. -gcflags="-m"
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- 63. @tyler_treat $ go test-bench=. -gcflags="-l"
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- 69. @tyler_treat@tyler_treat SSA backend & remainingtype conversions inlined x.(*T) inlined
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- 75. @tyler_treat $ go test-bench=. -gcflags="-S"
- 76. @tyler_treat $ go test-bench=. -gcflags="-S"
- 77. @tyler_treat $ go test-bench=. -gcflags="-S"
- 78. @tyler_treat Key Insight: If performancematters, write type-specific code.
- 79. @tyler_treat Overview - Measuring performance -Language features - Memory management - Concurrency and multi-core
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- 88. @tyler_treat How is sync.Poolso fast?
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- 93. @tyler_treat Overview - Measuring performance -Language features - Memory management - Concurrency and multi-core
- 94. @tyler_treat “We generally don’twant sync/atomic to be used at all…Experience has shown us again and again that very very few people are capable of writing correct code that uses atomic operations…” —Ian Lance Taylor
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- 96. @tyler_treat@tyler_treat Subscribers Messages Fast TopicMatching http://bravenewgeek.com/fast-topic-matching/
- 97. @tyler_treat@tyler_treat Subscribers Messages Fast TopicMatching http://bravenewgeek.com/fast-topic-matching/
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- 104. @tyler_treat@tyler_treat G1 G1 1. Assign ageneration, G1, to each I-node (empty struct). Ctrie
- 105. @tyler_treat 1. Assign ageneration, G1, to each I-node (empty struct). 2. Add new node by copying I-node with updated branch and generation then GCAS, i.e. atomically: - compare I-nodes to detect tree mutations. - compare root generations to detect snapshots. @tyler_treat G2 G1 Ctrie
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- 108. @tyler_treat The Go racedetector doesn’t protect you from doing dumb stuff.
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- 112. @tyler_treat Side note: unsafe is,in fact, unsafe.
- 113. @tyler_treat “Packages that import unsafe maydepend on internal properties of the Go implementation. We reserve the right to make changes to the implementation that may break such programs.” https://golang.org/doc/go1compat
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- 115. @tyler_treat Key Insight: Struct layoutcan make a big difference.
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- 149. @tyler_treat RWMutex1 RWMutex2 RWMutex3RWMutexN…memory 24 bytes
- 150. @tyler_treat RWMutex1 RWMutex2 RWMutex3RWMutexN…memory 24 bytes 64 bytes (cache line size)
- 151. @tyler_treat RWMutex1 RWMutex2 RWMutex3RWMutexN…memory 24 bytes 64 bytes (cache line size) Cache rules everything around me
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- 154. @tyler_treat padding … 64 bytes (cacheline size) memory 24 bytes RWMutex1 Cache rules everything around me
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- 158. @tyler_treat Go makes concurrency easyenough to be dangerous.
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- 160. @tyler_treat The standard libraryprovides general solutions (and they’re generally what you should use). 1
- 161. @tyler_treat Seemingly small, idiomatic decisionscan have profound performance implications. 2
- 162. @tyler_treat The Go toolchainhas lots of tools for analyzing your code—learn them. 3
- 163. @tyler_treat Go’s compiler andruntime continue to improve. 4
- 164. @tyler_treat Performance profile can changedramatically between releases. 5
- 165. @tyler_treat Relying on assumptions canbe fatal. 6
- 166. @tyler_treat Code is marginal, architectureis material. 7
- 167. @tyler_treat Peeking behind thecurtains can pay dividends. 8
- 168. @tyler_treat Above all, optimizefor the right trade-off. 9
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