How Fast is Spring? by Dave Syer at SpringOne Tour 2019 LND

1. How Fast is
Spring?Dave Syer, 2018
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
1 of 28 18/03/2019, 19:01

2. Agenda
How much work is Spring doing, compared to other parts of your app?
Tools for measurement
Comparison between various classpath and packaging choices
Speeding things up
The future
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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3. Baseline Micro App
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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4. Heap Memory and Garbage Collection
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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5. Garbage Collection
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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6. Flame Graph
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How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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7. all
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Spring Boot 2.0 Spring Boot 2.1
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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8. How Fast is Spring?
TL;DR How do I make my app go faster?
Classpath exclusions from Spring Boot web starters
Use the spring-context-indexer
Don’t use actuators if you can afford not to
Use Spring Boot 2.1 (or 2.2) and Spring 5.1
Use explicit spring.config.location
Switch off JMX: spring.jmx.enabled=false
Make bean definitions lazy by default
Unpack the fat jar and run with an explicit classpath
Run the JVM with -noverify. Also consider -XX:TieredStopAtLevel=1
Import autoconfigurations individually
Use functional bean definition
(Build a native image)
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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9. Summary
Spring was designed ab initio to be lightweight
The engineering team cares deeply about performance
There are many optional features
Packaging: exploded jar with application main is always best
Server: there is no measureable difference between Tomcat, Jetty and Undertow
Netty is a bit faster on startup - you won’t notice in a large app
The more features you use, the more classes are loaded
Functional bean definitions rule
Spring Boot, HTTP: starts in <1sec and uses <10MB heap
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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10. Tools
Benchmarks: JMH
JUnit and JMH: microbenchmark-runner
Profiling: async-profiler
GC pressure: JMC a.k.a. Flight Controller
Quick metrics for any Spring Boot jar: Benchmark launcher from dsyer/spring-boot-startup.
Classpath manipulation: Thin Launcher
Profiling with AspectJ
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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11. Benchmarks: Application Startup
Static benchmarks from https://github.com/dsyer/spring-boot-startup-bench. New JVM (separate
process) per application startup, explicit classpath (not fat jar).
class method sample beans classes heap memory median mean range
MainBenchmark main demo 121.000 5643.000 13.360 76.726 0.935 0.948 0.017
MainBenchmark main jdbc 156.000 5794.000 14.137 78.331 1.008 1.017 0.012
MainBenchmark main actr 222.000 6182.000 15.569 83.695 1.140 1.155 0.020
StripBenchmark strip slim 103.000 5465.000 13.815 76.140 0.875 0.897 0.041
StripBenchmark strip thin 62.000 5247.000 12.810 73.781 0.810 0.827 0.023
StripBenchmark strip lite 30.000 5012.000 11.432 70.928 0.715 0.727 0.012
StripBenchmark strip func 26.000 4967.000 11.351 70.516 0.686 0.701 0.026
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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12. Number of Classes vs. Startup Time
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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13. WebFlux and Micro Apps
Flux benchmarks from https://github.com/dsyer/spring-boot-startup-bench
class method sample beans classes heap memory median mean range
MainBenchmark main demo 93.000 4420.000 8.153 50.333 0.771 0.816 0.042
MainBenchmark main jlog 80.000 3649.000 6.540 44.006 0.685 0.712 0.046
MiniBenchmark boot jlog 28.000 3250.000 6.692 41.158 0.562 0.571 0.013
MiniBenchmark mini jlog 27.000 2986.000 5.421 38.561 0.516 0.524 0.014
MiniBenchmark micro jlog 2.000 2215.000 4.817 33.320 0.339 0.344 0.007
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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14. JVM Tweaks
Command line: -noverify -XX:TieredStopAtLevel=1
-Djava.security.egd=file:/dev/./urandom
Open J9: CDS -Xquickstart -Xshareclasses -Xscmx128m
Java 10/11: CDS, AOT (GraalVM)
Explicit classpath (exploded archive)
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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15. How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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16. Classpath Exclusions
YMMV, but consider excluding:
Jackson (spring-boot-starter-json)
Logback (spring-boot-starter-logging)
Hibernate Validator (org.hibernate.validator:hibernate-validator)
Actuators (spring-boot-starter-actuator)
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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17. Lazy Beans
Spring Data @EnableJpaRepositories(bootstrapMode=BootstrapMode.LAZY) or
spring.data.jpa.repositories.bootstrap-mode=lazy
Look carefully at custom beans with expensive @PostConstruct
Profiling with AspectJ
Lazy subsystems, E.g. see Lazy Actuator
Spring Boot 2.2: spring.main.lazy-initialization=true
Benchmark (sample) Mode Cnt Score Error Units Faster
MainBenchmark.main empt ss 10 0.495 ± 0.008 s/op 9.91%
MainBenchmark.main jlog ss 10 0.692 ± 0.017 s/op 21.04%
MainBenchmark.main demo ss 10 0.805 ± 0.016 s/op 19.45%
MainBenchmark.main actr ss 10 0.946 ± 0.021 s/op 27.03%
MainBenchmark.main jdbc ss 10 0.860 ± 0.010 s/op 19.95%
MainBenchmark.main actj ss 10 1.015 ± 0.020 s/op 29.11%
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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18. Manual Configuration
Choose your own autoconfigurations: "a la carte" instead of "all you can eat".
@SpringBootConfiguration
@ImportAutoConfiguration({
WebFluxAutoConfiguration.class,
ReactiveWebServerFactoryAutoConfiguration.class,
ErrorWebFluxAutoConfiguration.class,
HttpHandlerAutoConfiguration.class,
ConfigurationPropertiesAutoConfiguration.class,
PropertyPlaceholderAutoConfiguration.class
})
@RestController
public class DemoApplication {
...
}
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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19. PetClinic Benchmarks
Blue: out of the box Spring Boot.
Yello: manual autoconfiguration.
Red: fully functional via Spring Init
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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20. Functional Bean Definitions
Before:
@Configuration
public class SampleConfiguration {
@Bean
public Foo foo() {
return new Foo();
}
@Bean
public Bar bar(Foo foo) {
return new Bar(foo);
}
}
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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21. Functional Bean Definitions
After:
public class SampleConfiguration
implements ApplicationContextInitializer<GenericApplicationContext> {
public Foo foo() {
return new Foo();
}
public Bar bar(Foo foo) {
return new Bar(foo);
}
@Override
public void initialize(GenericApplicationContext context) {
context.registerBean(SampleConfiguration.class);
context.registerBean(Foo.class,
() -> context.getBean(SampleConfiguration.class).foo());
context.registerBean(Bar.class, () -> context.getBean(SampleConfiguration.class)
.bar(context.getBean(Foo.class)));
}
}
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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22. Result
C.f. Bunc vs Demo.
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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23. Examples
Micro apps (FuncApplication and BuncApplication): https://github.com/dsyer/spring-
boot-micro-apps
Spring Fu: https://github.com/spring-projects/spring-fu
Spring Init: https://github.com/spring-projects-experimental/spring-init
Spring Cloud Function spring.functional.enabled=true
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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24. CPU Constrained Environments
container cpus startup(ms)
===========================
riff 4 2817
scf 4 664
riff 2 4614
scf 2 653
riff 1 16782
scf 1 2121
scf:n 1 1091
riff is the image built by pack using the riff builder
scf same app built with WebFlux and functional beans
scf:n also switch off background preinit
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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25. Ahead of Time Compilation (AOT)
Native images can be very efficient (see Graal VM).
$ native-image -H:Name=target/bunc ... com.example.func.BuncApplication
$ ./target/bunc
. ____ _ __ _ _
/ / ___'_ __ _ _(_)_ __ __ _
( ( )___ | '_ | '_| | '_ / _` |
/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |___, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot ::
...
Aug 07, 2018 11:25:13 AM org.springframework.boot.web.embedded.netty.NettyWebServer start
INFO: Netty started on port(s): 8080
Aug 07, 2018 11:25:13 AM org.springframework.boot.StartupInfoLogger logStarted
INFO: Started application in 0.036 seconds (JVM running for 0.04)
Benchmark app started
Started HttpServer: 40ms
Downside: you lose all of JVM benefits (debugging, manageability, dynamic compilation,
optimization, garbage collection).
Also, too many issues still for general purpose use.
How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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26. How Fast is Spring? http://localhost:4000/decks/how-fast-is-spring.html
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27. Links
https://spring.io/team/dsyer - blogs
https://github.com/dsyer/spring-boot-startup-bench - older (back to Spring Boot 1.3), fat jar
data
/static benchmarks in the same repo - newer, explores classes loaded correlation
/flux benchmarks in the same repo - WebFlux
Spring Fu: https://github.com/spring-projects/spring-fu
Spring Init Experiment: https://github.com/spring-projects-experimental/spring-init
https://github.com/dsyer/spring-boot-allocations - explore functional beans and GC pressure
https://github.com/dsyer/spring-boot-micro-apps - functional beans and AOT (samples not
benchmarks)
https://github.com/dsyer/spring-boot-aot - AOT compilation and Graal VM
https://github.com/mp911de/microbenchmark-runner: Microbenchmark runner with JUnit
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28. ← →
1 / 23
Go to Slide: Go
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