Jason Greene [http://community.jboss.org/people/jason.greene] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631175#631175 -------------------------------------------------------------- Since MSC is a concurrent state machine it's thread pool is a critical resource that is intended to run only non-blocking (busy) tasks. Since there can be thousands of services, and MSC does not know the usage pattern of each service, it's not possible to have a single large generic thread pool for everything. For this reason services that need to execute blocking tasks must use async startup and pass those tasks to another thread pool. See the Service javadoc for more info: http://docs.jboss.org/jbossmsc/1.0.0.GA/api/org/jboss/msc/service/Service... http://docs.jboss.org/jbossmsc/1.0.0.GA/api/org/jboss/msc/service/Service... -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631175#631175] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

David Lloyd [http://community.jboss.org/people/dmlloyd] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631178#631178 -------------------------------------------------------------- You have to call context.complete() from within your asynchronous task.  No, you cannot use context.execute() for that; that uses a service thread.  You need a separate thread pool for blocking tasks. I think though that overall you might want to think about avoiding hooking into the AS at this level. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631178#631178] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Jason Greene [http://community.jboss.org/people/jason.greene] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631213#631213 -------------------------------------------------------------- Lifecycle.execute() reuses the same MSC thread pool, so blocking tasks are off limits there as well. It's facility is for uncommon use cases (arguably it shouldn't exist at all). If you want to do an async start task do the following steps: 1. In your start() method call LifecycleContext.asynchronous. This tells MSC not to assume a method return indicates completion 2. In your start() method create a Thread (or a pool depending on your use case). For example, Executors.newSingleThreadExecutor. 3. Construct a new instance of your blocking task and pass it a copy of the StartContext (LifeCyclecontext) 4. The task's run method should be written to perform the blocking task and call complete() on the Lifecycle context when done 5. Pass and execute the task instance to the pool/thread you created in step 2. This will cause your blocking operation to start in another thread 6. Return from your start method. What will happen after that point is that the service will remain in STARTING state until the task calls complete(), once that happens it will become available to other dependencies. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631213#631213] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631227#631227 -------------------------------------------------------------- One extra question though - let's say I have multiple tasks that can be blocking, then based on what you mentioned earlier I can use a thread pool to kickstart each task. So far so good. The question is : when to call "complete" ? Should I call complete on every thread that had a blocking operation ? Or I will have to make it one time after each thread finishes ? Just to complete such a case scenario and understand the full complexity. Thanks! -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631227#631227] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631234#631234 -------------------------------------------------------------- Great ! I already started to think for a lot more complex stuff for the complete .... :) I'll ask one more question - hopefully the last one. Let's assume that I have a WAR file that needs that service to be up. I know that I can programatically add "dependecies" towards WAR depolyment. So far so good. My question is: does the AS postpone the WAR file deployment until the service completes OR it will deploy it and then the WAR file will miss-behave (meaning throwing some kind of exceptions due to lack of access to the "late" service) ? And I think I am going over the full exercice :) of understanding how AS works on that level. Thanks! -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631234#631234] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631244#631244 -------------------------------------------------------------- OK - I guess I understand. So for example if I do : context.addStep( *new AbstractDeploymentChainStep() {* **     protected** **void** execute(DeploymentProcessorTarget processorTarget) {           processorTarget.addDeploymentProcessor(Phase.++DEPENDENCIES++, Phase.++DEPENDENCIES_MODULE++, **new** MyDependencyProcessor());      } ++RUNTIME++); }, OperationContext.Stage. And in MyDependencyProcessor I do:            ModuleSpecification moduleSpecification = deploymentUnit.getAttachment(Attachments. ++MODULE_SPECIFICATION++); ModuleDependency dep = **new** ModuleDependency(Module.+getBootModuleLoader+(), myModule.getIdentifier(), **false**, **false**, **false**);      dep.addExportFilter(PathFilters.+getMetaInfFilter+(), **true**);      dep.addImportFilter(PathFilters.+getMetaInfFilter+(), **true**);     moduleSpecification.addSystemDependency(dep); where myModule is the blocking service. Then if service still blocks at deployment, then all deployments would fail until the service is up, right ?  -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631244#631244] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Jason Greene [http://community.jboss.org/people/jason.greene] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631605#631605 -------------------------------------------------------------- Only the service itself can call asynchronous in it's start or stop method. As mentioned above, it must be called before the service method returns. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631605#631605] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631612#631612 -------------------------------------------------------------- I do have in the framework addService method : builder.addDependency(SubsystemState. ++SERVICE_NAME++,SubsystemState.**class**, service.injectedSubsystemState); So I do not understand something ... else ...  -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631612#631612] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Jason Greene [http://community.jboss.org/people/jason.greene] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631620#631620 -------------------------------------------------------------- Put another way this is the chain of events that should happen for it to work MSC Thread X:   MSC decides to start a service -> MSC calls your service.start() -> {        /* Not done yet! */ ctx.asynchronous();         passToSomeOtherThread(ctx);         return; }   SomeOtherThread: {     doStuff();     /* Tell MSC I am done */ ctx.complete(); } -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631620#631620] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Jason Greene [http://community.jboss.org/people/jason.greene] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631627#631627 -------------------------------------------------------------- Only ME.start can call startContext.asynchronous(). Having something else do it doesn't make much sense (either the method is asynchronous or it isn't). The only call that is ever intended to be done outside of the ME.start(SC) thread is complete() and that MUST be done after asynchronous is called. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631627#631627] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631631#631631 -------------------------------------------------------------- I got that. My problem is that when the ME.start() is called by the MSC - the SubsystemState did not build yet the module list: M1, M2 ! And thus when populating the model, SubsystemState will call addModule which in turn will do the WRONG stuff ! That is clear. Any idea what I doing wrong that the ME.start() gets called before the SubsystemState builds the list of modules ? I do not see why that happens. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631631#631631] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631639#631639 -------------------------------------------------------------- Yes - I am trying to build a 'very' basic module loader. Instead of having multiple application from my collegues writing their own ME, I could have one ME handling different module startups - obviously with very basic or restricted type of service functionality (like no ejb support within, etc ...) So, I think I have done that ok but it looks like I have some issues. The problem must be around here : SubsystemState: # **public** **static** ServiceController<SubsystemState> addService(ServiceTarget serviceTarget, Activation activation) {  // activation is forced to eager      SubsystemState state = **new** SubsystemState(); // will this be the object that will be injected into the FrameworkBootstrapService ?!?      state.setActivation(activation); #      ServiceBuilder<SubsystemState> builder = serviceTarget.addService(++SERVICE_NAME++, state); }; **protected** *void performBoottime(OperationContext context, ModelNode operation, ModelNode model, ServiceVerificationHandler verificationHandler, List<ServiceController<?>> newControllers) {      context.addStep(**new** AbstractDeploymentChainStep() { *      builder.setInitialMode(Mode.++ACTIVE++);      **return** builder.install()  SubsystemAdd: **     protected** **void**  execute(DeploymentProcessorTarget processorTarget) {            // Add deployment dependency on the WAR/RAR/SAR applications            processorTarget.addDeploymentProcessor(Phase. ++           DEPENDENCIES++, Phase.++DEPENDENCIES_MODULE++, **new** DependencyProcessor());      } }, OperationContext.Stage. ++RUNTIME++ ); ServiceTarget serviceTarget = context.getServiceTarget(); // Add the Subsystem State service - it will hold subsystem config. Activation is EAGER for both. newControllers.add(SubsystemState.+addService+(serviceTarget, getActivationMode(operation))); // Add the service - all modules will be handled via the service newControllers.add(FrameworkBootstrapService.+addService+(serviceTarget, verificationHandler)); So, to me, it looks like I am doing the right stuff. BUT ...... ##  } FrameworkBootstrapService: - +dependency towards the SubsystemState added+. *private ** **public** **static** ServiceController<FrameworkBootstrapService> addService(**final** ServiceTarget target, **final** ServiceListener<Object>... listeners) {FrameworkBootstrapService service = **new** FrameworkBootstrapService();ServiceBuilder<FrameworkBootstrapService> builder = target.addService( ++SERVICE_NAME++, service);builder.addDependency(SubsystemState. ++SERVICE_NAME++,SubsystemState.**class**, service.injectedSubsystemState);builder.addListener(listeners); **return** builder.install();} **final** InjectedValue<SubsystemState> injectedSubsystemState = **new** InjectedValue<SubsystemState>();* -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631639#631639] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631657#631657 -------------------------------------------------------------- Any idea how can I synchronize between the Framework bootstrap and the Add Operation Handler ? -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631657#631657] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Jason Greene [http://community.jboss.org/people/jason.greene] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631706#631706 -------------------------------------------------------------- Hmm I don't really follow. Do you just want the ability to create lightweight services from a deployment? We have a notion called a "service activator" which allows you to take any jar/war deployment and have it launch services when it is deployed. If you could describe the use case behind this I might be able to offer better suggestions. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631706#631706] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631834#631834 -------------------------------------------------------------- Let me take a different approach. When I create a ME I can define/build a subsystem having configration, properties, etc... The subsystem can have runtime changes via jboss-admin.sh. Any objections ? Now, the subsystem can be build when reading the standalone.xml file OR having a runtime subsystem state - at my understanding. Any objections ? Then the subsystem state is updated at rutime via OperationStepHandler && "registerOperationHandler(ModelDescriptionConstants.+ADD .....",+ etc. Now, my question is how a ME service can get the subsystem state after the all operation handlers on that subsystem have been performed ?  -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631834#631834] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631985#631985 -------------------------------------------------------------- Yes - that works ok. The issue that I have is that one "add" operation comes after my framework start and I am getting a concurrent exception when accessing a list built within the subsystem state. Here are the traces that I am getting : 23:54:32,026 INFO  [<myPkg>.TestSubsystemAdd] (Controller Boot Thread) Activating Test Subsystem 23:54:32,031 INFO  [<myPkg>.MyBootstrapService] (Controller Boot Thread) Test MyBootstrapService - created 23:54:32,031 INFO  [<myPkg>.MySubsystemState] (MSC service thread 1-3) MySubsystemState - started 23:54:32,031 INFO  [<myPkg>.TestAdd] (Controller Boot Thread) TestAdd --> execute Add                                  <<<<< this is OK 23:54:32,031 INFO  [<myPkg>.MyBootstrapService] (MSC service thread 1-10) Test MyBootstrapService - starting. 23:54:32,032 INFO  [<myPkg>.MyBootstrapService] (MSC service thread 1-10) Test MyBootstrapService - started in:0ms. 23:54:32,033 INFO  [<myPkg>.TestAdd] (Controller Boot Thread) TestModuleAdd --> execute Add                       <<<<< that comes out of sync  I do not understand why the last execute Add occurs AFTER the bootstrapservice started. And I am wondering how this is getting synchronized between the MSC service thread && the Controller Boot Thread. I do not get where I am messing it up ! I used the proper dependency when I add the bootstrap service towards the runtime subsystem state. If you have an idea - it will be more than welcomed. BR, Dan S. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631985#631985] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Dan Sirbu [http://community.jboss.org/people/lmcdasi] created the discussion "Re: can I avoid a service to block as7 startup ?" To view the discussion, visit: http://community.jboss.org/message/631635#631635 -------------------------------------------------------------- Yes - I commented out the addModule and the FrameworkBootstrap does not get the list of modules: server.log 12:46:49,376 INFO  [<mypkg>.SubsystemAdd] (Controller Boot Thread) Activating Test Subsystem 12:46:49,380 INFO  [<mypkg>.FrameworkBootstrapService] (Controller Boot Thread) Test FrameworkBootstrapService - created 12:46:49,381 INFO  [<mypkg>.FrameworkBootstrapService] (MSC service thread 1-15) Test FrameworkBootstrapService - started. <NOTHING - which means that the module list is empty> 12:46:49,404 INFO  [org.jboss.as.jmx.JMXConnectorService] (MSC service thread 1-16) Starting remote JMX connector 12:46:49,408 INFO  [org.jboss.as.ee] (Controller Boot Thread) Activating EE subsystem boot.log 12:46:48,559 INFO  [<mypkg>.TestExtension] TestSubsystemParser --> readElement 12:46:48,561 INFO  [<mypkg>.TestExtension] TestSubsystemParser --> parseModulesElement 12:46:48,797 INFO  [<mypkg>.TestExtension] TestExtension --> Activating TestExtension 12:46:48,800 INFO  [<mypkg>.TestExtension] TestExtension --> Activating Testpreloaded modules 12:46:48,845 INFO  [<mypkg>.TestSubsystemAdd] TestSubsystemAdd --> populateModel 12:46:48,845 INFO  [<mypkg>.TestModuleAdd] TestModuleAdd --> execute add 12:46:48,846 INFO  [<mypkg>.TestModuleAdd] TestModuleAdd --> execute add  -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/631635#631635] Start a new discussion in JBoss AS7 Development at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]