Tuesday, November 7, 2017

Increase your JSF application performance - Version 2017

As my last posts are already 5 years old, i think it's time for a new one :D

Environment:


If you would like to use a JavaEE application server, i would go with TomEE.
It's the fastest and smallest application server available and already comes with Apache MyFaces as JSF implementation and Apache OpenWebBeans as CDI implementation.

There are already really good benchmarks available why we should choose MyFaces over Mojarra and OpenWebBeans over Weld:

Understanding JSF 2.0 Performance – Part 1
Understanding JSF 2.0 Performance – Part 2
Understanding JSF 2.0 Performance – Part 3
CDI Performance

So if you just use a plain servlet container like Tomcat or Jetty, i would also use MyFaces and OpenWebBeans.

In the past it was also a good performance boost if you use JUEL over Tomcat's EL implementation - sadly JUEL doesn't implement EL 3.0.

    Configuration:


    • Common settings:
    • <context-param>
          <param-name>javax.faces.PROJECT_STAGE</param-name>
          <param-value>Production</param-value>
      </context-param>
      <context-param>
          <param-name>javax.faces.FACELETS_REFRESH_PERIOD</param-name>
          <param-value>-1</param-value>
      </context-param>
      <context-param>
          <param-name>javax.faces.STATE_SAVING_METHOD</param-name>
          <param-value>server</param-value>
      </context-param>
    • Prioritize OpenWebBeans in MyFaces:
    • <context-param>
          <param-name>org.apache.myfaces.EL_RESOLVER_COMPARATOR</param-name>
          <param-value>org.apache.myfaces.el.unified.OpenWebBeansELResolverComparator</param-value>
      </context-param>
    • Enable ViewPooling: http://lu4242.blogspot.de/2013/12/view-pooling-in-jsf-22-using-apache.html 
    • NOTE: You must also set:
      <context-param>
          <param-name>org.apache.myfaces.CACHE_EL_EXPRESSIONS</param-name>
          <param-value>alwaysRecompile</param-value>
      </context-param>
    • Enable WhiteSpace compression: http://lu4242.blogspot.de/2012/12/html-white-space-compression-for-jsf.html
    • Disable JSP support in MyFaces - this increases the startup performance (Attention - the ExpressionFactory might differ e.g. on Glassfish or Wildfly):
    • <context-param>
          <param-name>org.apache.myfaces.SUPPORT_JSP_AND_FACES_EL</param-name>
          <param-value>false</param-value>
      </context-param>
      <context-param>
          <param-name>org.apache.myfaces.EXPRESSION_FACTORY</param-name>
          <param-value>org.apache.el.ExpressionFactoryImpl</param-value>
      </context-param> 
    • Disable ManagedBeans support (since 2.3):
      <context-param>
          <param-name>org.apache.myfaces.SUPPORT_MANAGED_BEANS</param-name>
          <param-value>false</param-value>
      </context-param>
    • Reduce saved view states:
      <context-param>
          <param-name>org.apache.myfaces.NUMBER_OF_VIEWS_IN_SESSION</param-name>
          <param-value>15</param-value>
      </context-param>
      <context-param>
          <param-name>org.apache.myfaces.NUMBER_OF_SEQUENTIAL_VIEWS_IN_SESSION</param-name>
          <param-value>3</param-value>
      </context-param> 
    • Disable ViewState compression (better performance but more memory usage):
      <context-param>
          <param-name>org.apache.myfaces.COMPRESS_STATE_IN_SESSION</param-name>
          <param-value>false</param-value>
      </context-param>
    • Enable partial submit in PrimeFaces - this reduces the network traffic:
      <context-param>
          <param-name>primefaces.SUBMIT</param-name>
          <param-value>partial</param-value>
      </context-param>
    • Move above the fold scripts to the bottom (end of body). This is a huge improvement of the visible rendering and removes flickering between navigations (since 6.2):
      <context-param>
          <param-name>primefaces.COLLECT_SCRIPTS</param-name>
          <param-value>true</param-value>
      </context-param>
    • Other params to increase performance:
    • <context-param>
          <param-name>org.apache.myfaces.CHECK_ID_PRODUCTION_MODE</param-name>
          <param-value>false</param-value>
      </context-param>
      <context-param>
          <param-name>org.apache.myfaces.VIEW_UNIQUE_IDS_CACHE_ENABLED</param-name>
          <param-value>true</param-value>
      </context-param>
      <context-param>
          <param-name>org.apache.myfaces.COMPONENT_UNIQUE_IDS_CACHE_SIZE</param-name>
          <param-value>500</param-value>
      </context-param>
      <context-param>
          <param-name>org.apache.myfaces.PRETTY_HTML</param-name>
          <param-value>false</param-value>
      </context-param>
      <context-param>
          <param-name>org.apache.myfaces.EARLY_FLUSH_ENABLED</param-name>
          <param-value>true</param-value>
      </context-param>
    • Use a custom ServletFilter to set the correct expires/cache headers of your resources (images, stylesheets, javascripts). This is only required if you don't use the JSF resource handling for every resource. The JSF impl should already do it correctly for all JSF managed resources.
    • Compress and optimize your Javascripts in your build process. If you use maven, try primefaces-extensions' closure compiler maven plugin.

    Patterns:


    • Correctly define update/render and process/execute! Often this is a huge improvement as many times the whole form is updated instead only a small part. But i also prefer maintainability over performance here.
    • If you don't use ViewScoped beans, it's a good but small improvement to mark the view as stateless via transient=true.
    • Try using HTML over JSF tags.
      • Especially avoid using h:outputText if you don't need the escaping. Just use EL expressions inside your xhtml template.
      • The same applies for some other components like p:outputPanel. Just use a plain div. If you need to make it updateable, you can still use "passtrough elements" (<div jsf:id="...">...</div>)
    • Never put logic in getters because they can be called multiple times - especially for the rendered attribute!
    • Avoid logic (like inline if-statements) in EL expression! It's better to move those logic into the bean. It's faster and often easier to read and maintain.
    • Prefer AJAX over a full postback!
    • Cache data, which is required multiple times in the same view, in @RequestScoped beans.
    • Avoid missusing @SessionScoped, @ViewScoped and other long living scopes if not really required. 
    • Try to put only small amount of data in such long living beans. Sometimes a small flag or id of an entity is enough information. Often people put many entities in such long living beans. One of my patterns is to split beans into *Controllers (@RequestScoped) and *StateHolders (@ViewScoped, @ViewAccessScoped). *StateHolders are just data containers.

    Monday, January 25, 2016

    Enable failover with OpenWebBeans (>= 1.5.1)

    Since OWB 1.5.1 you don't need any configuration or FailOverFilter anymore as the beans are directly stored in the HttpSession :)

    Saturday, September 21, 2013

    Session replication / clustering / failover with Tomcat (Part 1 - Overview)

    This is my first post of a series about Tomcat and clustering.
    In this post i will explain some different replication mechanism.


    NOTE: A common drawback of replication, like it's defined in the specs, is that only HttpSession#setAttribute(...) triggers replication.
    This means that if you store a container object in the session and if you change a variable inside the object, you must HttpSession#setAttribute(...) again to replicate the modified object again.
    Many frameworks implements a simple workaround for it - i will write about it another post.


    All to all replication / DeltaManager 


    With this mode, Tomcat just replicates the session to all registered nodes.



    Pro:
    • No single point of failure at software level
    • Every node holds all sessions
    • In theory, all other nodes can be turned off
    • No extra software is needed
    • Synchronous or Asynchronous replication
    • Open Source
    • Enterprise-Support available
    Contra:
    • High memory usage and network traffic because all nodes holds all sessions
    • Objects which are stored in the session must be triggered manually to replicate again if a property has been changed
    • Slower session serialization



    Primary/Secondary Replication (Buddy Replication) / BackupManager


    The sessions will be replicated to the next neighbor. If one Tomcat is not available anymore, the neighbor still holds the sessions.



     Pro:
    • No single point of failure at software level
    • Lower memory usage and network traffic because the session is not stored on all nodes
    • No extra software is needed
    • Synchronous or Asynchronous replication
    • Open Source
    • Enterprise-Support available
     Contra:
    • Not quite as battle tested as the All-to-all replication (see Tomcat documentation)
    • Objects which are stored in the session must be triggered manually to replicate again if a property has been change
    • Slower session serialization



    Memcached-session-manager


    Each Tomcat replicates all sessions to N (multiple) Memcached nodes.
    If a session is not available on the local Tomcat, the memcached-session-manager tries to lookup the session from the Memcached nodes.



     Pro:
    • No single point of failure at software level
    • More scalability
    • Session will be replicated to N “Memcached” nodes – The sessions are still available if all webservers are down
    • Automatically handles “Memcached” nodes failover
    • Sticky mode: Lower memory usage because every node holds only the current used sessions
    • Non-Sticky mode: Lowest memory usage because Tomcat does not hold the sessions anymore. Session will be received from memcached for each request
    • MSM will automatically trigger replication if a property in a session stored object has been changed
    • Faster session serialization – Changeable mechanism
    • Synchronous or Asynchronous replication
    • Open Source
    • Enterprise-Support available for Tomcat
     Contra:
    • Extra software needed (“Memcached” plugin and nodes)
    • Cannot switch to another Java Webserver which does not automatically check changed values in the session - but only if the used framework has no implemented workaround
    • AFAIK no Enterprise-Support available for the Memcached plugin but Martin Grotzke is very active on the mailing list

    Thursday, September 19, 2013

    Enable failover with OpenWebBeans (> 1.2.0)

    In my first post i already explained how it's possible to enable failover (aka clustering) with OpenWebBeans > 1.1.3: Enable failover with OpenWebBeans (> 1.1.3)

    Because we moved the clustering logic to own module, we must include this module since OWB 1.2.0:
    <dependency>
        <groupId>org.apache.openwebbeans</groupId>
        <artifactId>openwebbeans-clustering</artifactId>
    </dependency>

    You still need the org.apache.webbeans.web.failover.FailOverFilter but if you include this module, you must NOT add a custom openwebbeans.properties anymore. It will be registered automatically.

    Wednesday, September 18, 2013

    PrimeFaces Extensions 1.0

    This week, Oleg released a RC of PrimeFaces Extensions as you can read here: PrimeFaces Extensions 1.0.0.RC1 released

    To be honest, i had not much time to improve anything in PrimeFaces Extensions.
    I'm PrimeFaces committer since January 2013 and it was more fun to implement new features, working on complex stuff together with Çağatay or improve performance directly in PrimeFaces Core.
    I also will blog about some of this features the next weeks.

    The biggest of my changes in PrimeFaces Extensions 1.0 are the PrimeFaces 4.0 compatibility and a new CKEditor version (4.2.1 now).

    It's not sooo easy to marry CKEditor and the resource handling of JSF. I had to adjust some of there code and created some issues on their side.
    If they will improve it and fix those issues, updating CKEditor will much easier in the future.
    CKEditor removed and introduced new skins. Supported skins are "kama" and "moono" now.

    We also added support for "my" new Search Expression Framework of PrimeFaces 4.0 in all our components.

    We were also able to clean up some code because i could move some features or API changes directly to PrimeFaces Core.

    Stay tuned for the final release!

    Friday, December 14, 2012

    Dynamical switching of JSF state saving method

    By default, it's only possible to configure the state saving method (client or server) globally for all views in your application.

    This is sometimes really annoying as server side performs better but needs more memory.
    Also with server side state saving, it's not possible to cache views (if they have actions) because you will get a ViewExpiredException soon.

    So what about using client-side state for some views and using server-side state for all other views?

    Currently this is only possible with MyFaces (since 2.1.9). Mojarra doesn't support this feature.
    I created a specifiation improvement ticket (http://java.net/jira/browse/JAVASERVERFACES_SPEC_PUBLIC-1147) and hopefully this will be supported in Mojarra soon.

    So how can we use this feature?

    To switch the state saving method, we just need to overwrite/wrap the following method: StateManager#isSavingStateInClient(FacesContext).

    In my application i combined this feature with CODI ViewConfig.

    Create a ViewMetaData:
    @Inherited
    @ViewMetaData(override = true)
    @Target(ElementType.TYPE)
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    public @interface StateSaving {
    
      Method value();
    
      enum Method {
       SERVER,
       CLIENT
      }
    }
    

    Wrap the StateManager:
    public class ExtensionsStateManager extends StateManagerWrapper {
    
      @Override
      public boolean isSavingStateInClient(final FacesContext context) {
        boolean isSavingStateInClient;
    
        final StateSaving stateSaving = getStateSavingAnnotationViaCodiViewConfigResolver(context);
        if (stateSaving == null) {
          isSavingStateInClient = getWrapped().isSavingStateInClient(context);
        } else {
          isSavingStateInClient = stateSaving.value() == StateSaving.Method.CLIENT;
        }
    
        return isSavingStateInClient;
      }
    }
    

    Configure that JSF should use our StateManager:
    <?xml version="1.0" encoding="UTF-8"?>
    <faces-config xmlns="http://java.sun.com/xml/ns/javaee"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd"
      version="2.0">
      <application>
        <state-manager>xxx.xxx.ExtensionsStateManager</state-manager>
      </application>
    </faces-config>
    

    Usage:
    @Page(navigation = NavigationMode.REDIRECT)
    public interface Pages extends ViewConfig {
    
      @Page
      @StateSaving(Method.SERVER)
      class ViewA implements Pages { }
     
      @Page
      @StateSaving(Method.CLIENT)
      class View implements Pages { }
    }


    Currently i'm not a member of a library/framework, where i could add this nice feature.
    Maybe i will release my own lib for such stuff someday.

    Thursday, October 25, 2012

    Speedup jetty-maven-plugin startup time

    • Create a own profile - this allows more flexibility
    • <profile>
          <id>jetty-run</id>
      </profile>
      
    • Add jetty-maven-plugin to the profile. We also configure the plugin to get all resources from the src directory and only scan the java sources
    • <plugin>
          <groupId>org.mortbay.jetty</groupId>
          <artifactId>jetty-maven-plugin</artifactId>
          <configuration>
              <webAppSourceDirectory>${basedir}/src/main/webapp</webAppSourceDirectory>
              <scanIntervalSeconds>2</scanIntervalSeconds>
              <scanTargets>
                  <scanTarget>src/main/java</scanTarget>
              </scanTargets>
          </configuration>
          <executions>
              <execution>
                  <phase>package</phase>
                  <goals>
                      <goal>run</goal>
                  </goals>
              </execution>
          </executions>
      </plugin>
      
    • Skip unit testing via profile property
    • <properties>
          <maven.test.skip>true</maven.test.skip>
      </properties>
      
    • Skip building the WAR file
    • <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-war-plugin</artifactId>
          <executions>
              <execution>
                  <id>default-war</id>
                  <phase>none</phase>
              </execution>
          </executions>
      </plugin>
      
    • If you optimize and aggregate your javascript or CSS files, skip this too! Compression of this files is on localhost just prevents debugging. We created an own servlet which merges the files on-the-fly. Changes on JS or CSS will be also available after F5 in your browser - that's the nice side effect of the servlet :)
      • Skip optimzation (we use the primefaces-extensions plugin for this)
      • <plugin>
            <groupId>org.primefaces.extensions</groupId>
            <artifactId>resources-optimizer-maven-plugin</artifactId>
            <executions>
                <execution>
                    <id>optimize</id>
                    <phase>none</phase>
                </execution>
            </executions>
        </plugin>
        
      • Create a servlet to merge the resources (we also implemented a init-param called includeDirectory to read all source files)
      • @Override
        protected void doGet(final HttpServletRequest request, final HttpServletResponse response)
            throws ServletException, IOException
        {
            final OutputStream ouputStream = response.getOutputStream();
            response.setContentType(getServletConfig().getInitParameter("contentType");
        
            final List<File> filesToMerge = getFiles(getServletContext().getRealPath(getServletConfig().getInitParameter("includeDirectory")));
        
            for (final File fileToMerge : filesToMerge) {
            final FileInputStream inputStream = new FileInputStream(fileToMerge);
                IOUtils.copy(inputStream, ouputStream);
                inputStream.close();
            }
        
            ouputStream.close();
        }
        
        
      • For example, if your optimizer plugin aggregates your javascript files to "/javascript/bundle.js", we must overwrite this URL via a servlet mapping.
        We just create a second web.xml (this is just for localhost and jetty) with the name "web-localhost.xml" in your "src/main/webapp/WEB-INF" directory with the following servlet mapping
      • <servlet>
            <servlet-name>Merge Javascript Servlet</servlet-name>
            <servlet-class>xxx.servlet.MergeResourceServlet</servlet-class>
            <init-param>
                <param-name>includeDirectory</param-name>
                <param-value>/javascript/</param-value>
            </init-param>
            <init-param>
                <param-name>contentType</param-name>
                <param-value>application/x-javascript</param-value>
            </init-param>
        </servlet>
        <servlet-mapping>
            <servlet-name>Merge Javascript Servlet</servlet-name>
            <url-pattern>/javascript/bundle.js</url-pattern>
        </servlet-mapping>
        
      • Now we configure jetty to use our "web-localhost.xml" as overrideDescriptor
      • <plugin>
            <groupId>org.mortbay.jetty</groupId>
            <artifactId>jetty-maven-plugin</artifactId>
            <configuration>
                <webAppConfig>
                    <overrideDescriptor>src/main/webapp/WEB-INF/web-localhost.xml</overrideDescriptor>
                </webAppConfig>
                ...
            </configuration>
        </plugin>
    Finished! You will be able to start jetty now via "mvn package -P jetty-run".