Spring-boot slow to start - jhipster

Question

When I launch my jhipster app using "mvn spring-boot:run", it takes up to 60 seconds to start...
First part of my log is :
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building jhipster 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> spring-boot-maven-plugin:1.1.9.RELEASE:run (default-cli) # jhipster >>>
[INFO]
[INFO] --- maven-enforcer-plugin:1.3.1:enforce (enforce-versions) # jhipster ---
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) # jhipster ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 4 resources
[INFO] Copying 22 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) # jhipster ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) # jhipster ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 3 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) # jhipster ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] <<< spring-boot-maven-plugin:1.1.9.RELEASE:run (default-cli) # jhipster <<<
[INFO]
[INFO] --- spring-boot-maven-plugin:1.1.9.RELEASE:run (default-cli) # jhipster ---
[INFO] Attaching agents: []
Listening for transport dt_socket at address: 5005
--> Then it hangs for around 30 seconds before continuing :
[INFO] com.mycompany.myapp.Application - Starting Application on MacBook-Pro.local with PID 5130 (/Users/othomas/Developpement/jhipster-1.9.0/target/classes started by othomas in /Users/othomas/Developpement/jhipster-1.9.0)
[DEBUG] com.mycompany.myapp.Application - Running with Spring Boot v1.1.9.RELEASE, Spring v4.0.8.RELEASE
[DEBUG] org.jboss.logging - Logging Provider: org.jboss.logging.Log4jLoggerProvider
...
I remember having used older versions of jhipster generator (0.17 etc) et it started in 15-20 seconds.
Is it normal or is there a problem on my side ? Where to look for ?
Thanks,
O.

Answer 1

I've been suffering slow startup times myself and wondering what the cause was. I get all the console messages saying various things have started and then it hangs just before the final message to say the app has loaded.
Eventually I found I could use Java VisualVM as part of the JDK to see what was going on. If you have the jdk installed its jvisualvm.exe in the bin folder. Then when I select to debug as Application.java the tomcat process pops up and you can track what's going on.
I took a couple of thread dumps where it hangs and it always seemed to be where the swagger API docs are being generated. A bit more digging and this is configured in a class called MetricsConfiguration which is excluded if you run with a profile called "fast".
In eclipse I edited my debug configuration to include a program argument of:
--spring.profiles.active=dev,fast
This cuts down the startup time from 230 seconds to just 25!
I had a quick scan and fast seems to disable all sorts of things. It mainly looks like the stuff under the admin menu which you'll probably not need during development anyway. Personally I would prefer a fast bootup to being able to see the rest docs during development.
Swagger being such a hog made me wonder if it's such a good idea after all. Is it worth the cost? i then read this http://java.dzone.com/articles/swagger-great and I'm considering just removing it altogether. It's a nice idea but seems to add 33mb to the build + for me was causing really slow startup times.
For info I have around 16 entities. So not small but not excessively large either.

Answer 2

Make sure you aren't running the server in debug mode and have a breakpoint set. This reduced the startup time of one of my applications from 3 min to 22 sec.

Answer 3

This is weird.
Indeed, it should start in 5-15 seconds depending on your machine and specific setup.
But it should not hang for 30 seconds: the line you show is a bit new, it's because we launch the application in debug mode when you use the dev profile -> you can attach a debugger on it.
It looks like it's waiting for you to connect a debugger: I've never seen it myself, so maybe you have some specific JVM option for attaching a debugger at start up, with a timeout of 30 seconds?

Answer 4

Thanks for your feedback. I investigated and put more logs in the app (Application.java).
Actually the problem does not come from the debug mode, the application does not hang here.
The first big "pause" comes from the scanning of liquibase packages (addLiquibaseScanPackages(); in Application.java ) : 26 seconds !
My second pause is still related to Liquibase (log "Configuring Liquibase" ) : 20 seconds. During that time, if I put Liquibase log level to DEBUG, I see that a lock is set and then released but it happens very quickly.
I really don't understand. I am using h2 in-memory database, jdk 1.7.0_25 and Maven 3.0.5, running on MacBook Pro with SSD.
Here is my full log when I run with "mvn spring-boot:run".
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building jhipster 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> spring-boot-maven-plugin:1.1.9.RELEASE:run (default-cli) # jhipster >>>
[INFO]
[INFO] --- maven-enforcer-plugin:1.3.1:enforce (enforce-versions) # jhipster ---
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) # jhipster ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 4 resources
[INFO] Copying 22 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) # jhipster ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) # jhipster ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 3 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) # jhipster ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] <<< spring-boot-maven-plugin:1.1.9.RELEASE:run (default-cli) # jhipster <<<
[INFO]
[INFO] --- spring-boot-maven-plugin:1.1.9.RELEASE:run (default-cli) # jhipster ---
[INFO] Attaching agents: []
Listening for transport dt_socket at address: 5005
Wed Nov 26 16:32:23 CET 2014 Added log : Application is about to start
Wed Nov 26 16:32:28 CET 2014Added log : Application started, now we set banner to false
Wed Nov 26 16:32:28 CET 2014Added log : About to add Default profile
Wed Nov 26 16:32:28 CET 2014Added log : Default Profile added. Now we scan liquibase packages
Wed Nov 26 16:32:28 CET 2014Added log : Liquibase pakages scanned. Now we run the app
2014-11-26 16:32:54,564 [INFO] com.mycompany.myapp.Application - Starting Application on MacBook-Pro.local with PID 25452 (/Users/othomas/Developpement/jhipster-1.9.0/target/classes started by othomas in /Users/othomas/Developpement/jhipster-1.9.0)
2014-11-26 16:32:54,567 [DEBUG] com.mycompany.myapp.Application - Running with Spring Boot v1.1.9.RELEASE, Spring v4.0.8.RELEASE
2014-11-26 16:32:57,429 [DEBUG] org.jboss.logging - Logging Provider: org.jboss.logging.Log4jLoggerProvider
2014-11-26 16:32:57,559 [DEBUG] com.mycompany.myapp.config.AsyncConfiguration - Creating Async Task Executor
2014-11-26 16:32:58,305 [DEBUG] com.mycompany.myapp.config.MetricsConfiguration - Registering JVM gauges
2014-11-26 16:32:58,379 [INFO] com.mycompany.myapp.config.MetricsConfiguration - Initializing Metrics JMX reporting
2014-11-26 16:32:58,445 [DEBUG] com.mycompany.myapp.config.DatabaseConfiguration - Configuring Datasource
2014-11-26 16:32:59,353 [DEBUG] com.mycompany.myapp.config.DatabaseConfiguration - Configuring Liquibase
2014-11-26 16:33:19,489 [DEBUG] com.mycompany.myapp.config.CacheConfiguration - Starting Ehcache
2014-11-26 16:33:19,491 [DEBUG] com.mycompany.myapp.config.CacheConfiguration - Registering Ehcache Metrics gauges
2014-11-26 16:33:23,419 [DEBUG] com.mycompany.myapp.config.MailConfiguration - Configuring mail server
2014-11-26 16:33:24,559 [INFO] com.mycompany.myapp.config.WebConfigurer - Web application configuration, using profiles: [dev]
2014-11-26 16:33:24,560 [DEBUG] com.mycompany.myapp.config.WebConfigurer - Initializing Metrics registries
2014-11-26 16:33:24,564 [DEBUG] com.mycompany.myapp.config.WebConfigurer - Registering Metrics Filter
2014-11-26 16:33:24,565 [DEBUG] com.mycompany.myapp.config.WebConfigurer - Registering Metrics Servlet
2014-11-26 16:33:24,567 [DEBUG] com.mycompany.myapp.config.WebConfigurer - Registering GZip Filter
2014-11-26 16:33:24,569 [DEBUG] com.mycompany.myapp.config.WebConfigurer - Initialize H2 console
2014-11-26 16:33:24,570 [INFO] com.mycompany.myapp.config.WebConfigurer - Web application fully configured
2014-11-26 16:33:29,753 [INFO] com.mycompany.myapp.Application - Running with Spring profile(s) : [dev]
2014-11-26 16:33:30,012 [INFO] com.mycompany.myapp.config.ThymeleafConfiguration - loading non-reloadable mail messages resources
2014-11-26 16:33:30,896 [DEBUG] com.mycompany.myapp.aop.logging.LoggingAspect - Enter: com.mycompany.myapp.repository.CustomAuditEventRepository.auditEventRepository() with argument[s] = []
2014-11-26 16:33:30,905 [DEBUG] com.mycompany.myapp.aop.logging.LoggingAspect - Exit: com.mycompany.myapp.repository.CustomAuditEventRepository.auditEventRepository() with result = com.mycompany.myapp.repository.CustomAuditEventRepository$1#1edce963
2014-11-26 16:33:37,229 [INFO] com.mycompany.myapp.Application - Started Application in 68.311 seconds (JVM running for 73.972)
Wed Nov 26 16:33:37 CET 2014Added log : App is running
Thanks,
Olivier

Answer 5

It is advised to start the application with the debug points disabled unless you want to debug while starting up

Answer 6

you can just modify xmx like java -jar -Xmx1024m.
Because when Spring boot started, it loads lots of spring bean. You can add heap memory to improve it's performance.