Will do! Regards, Mariangela
*Mariangela Hills* Senior Technical Writer - WSO2, Inc. http://wso2.com Committer and PMC member - Apache Stratos email:mariang...@wso2.com | mobile: +94 773 500185 On Wed, Jun 24, 2015 at 2:43 PM, Reka Thirunavukkarasu <r...@wso2.com> wrote: > Thanks for implementing this nice feature Imesh. This helps a lot in > identifying the locking issues. > > @Mari, > > Can we add this to our documentation under developer guide or troubleshoot > section? So that it will help in debugging purpose. > > Thanks, > Reka > > On Tue, Jan 20, 2015 at 10:26 PM, Dakshika Jayathilaka <daksh...@wso2.com> > wrote: > >> Great Work imesh.. This will help to developers in many ways.. >> >> Better if we can add this to developer guide. >> >> *Dakshika Jayathilaka* >> Software Engineer >> WSO2, Inc. >> lean.enterprise.middleware >> 0771100911 >> >> On Tue, Jan 20, 2015 at 7:08 PM, Imesh Gunaratne <im...@apache.org> >> wrote: >> >>> Above issue is now fixed with commit revision: >>> fe0e6f81a673d6db815a56a3592c41441c4be3ae >>> >>> On Tue, Jan 20, 2015 at 7:03 PM, Imesh Gunaratne <im...@apache.org> >>> wrote: >>> >>>> Following JIRA explains the above problem found in 4.1.0-alpha: >>>> https://issues.apache.org/jira/browse/STRATOS-1089 >>>> >>>> On Tue, Jan 20, 2015 at 6:50 PM, Imesh Gunaratne <im...@apache.org> >>>> wrote: >>>> >>>>> Hi Devs, >>>>> >>>>> Currently we have significant amount of read write locks in Stratos >>>>> codebase to synchronize data structure updates made by multiple threads. >>>>> >>>>> As I figured out recently there are several possibilities that these >>>>> locks could cause problems if not properly implemented: >>>>> >>>>> *Problem 1: A thread trying to acquire a write lock while having a >>>>> read lock.* >>>>> *Problem 2: Locks acquired but not released* >>>>> >>>>> I just implemented a ReadWriteLock class in stratos common module >>>>> which could detect these problems. This class make use >>>>> of java.util.concurrent.locks.ReentrantReadWriteLock and implements >>>>> additional logic to detect problems. By default problem 2 detection logic >>>>> is disabled, it can be enabled by setting following system property: >>>>> >>>>> >>>>> *read.write.lock.monitor.enabled=true* >>>>> >>>>> I have now updated all read write locks with the above class. >>>>> Following is an example scenario where I detected an unreleased lock >>>>> in the REST API: >>>>> >>>>> org.apache.stratos.common.exception.LockNotReleasedException >>>>> at >>>>> org.apache.stratos.common.concurrent.locks.ReadWriteLockMonitor.checkTimeout(ReadWriteLockMonitor.java:71) >>>>> at >>>>> org.apache.stratos.common.concurrent.locks.ReadWriteLockMonitor.run(ReadWriteLockMonitor.java:50) >>>>> at >>>>> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) >>>>> at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:304) >>>>> at >>>>> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:178) >>>>> at >>>>> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) >>>>> at >>>>> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) >>>>> at >>>>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) >>>>> at java.lang.Thread.run(Thread.java:745) >>>>> [2015-01-20 18:30:12,952] ERROR >>>>> {org.apache.stratos.common.concurrent.locks.ReadWriteLockMonitor} - >>>>> System >>>>> error, lock has not released for 30 seconds: [lock-name] topology >>>>> [lock-type] Read [thread-id] 405 [thread-name] http-nio-9443-exec-21 >>>>> [stack-trace] >>>>> java.lang.Thread.getStackTrace(Thread.java:1589) >>>>> >>>>> org.apache.stratos.common.concurrent.locks.ReadWriteLock.acquireReadLock(ReadWriteLock.java:160) >>>>> >>>>> org.apache.stratos.messaging.message.receiver.topology.TopologyManager.acquireReadLockForCluster(TopologyManager.java:173) >>>>> >>>>> org.apache.stratos.rest.endpoint.api.StratosApiV41Utils.addClustersInstancesToGroupInstanceBean(StratosApiV41Utils.java:1015) >>>>> >>>>> org.apache.stratos.rest.endpoint.api.StratosApiV41Utils.setSubGroupInstances(StratosApiV41Utils.java:1027) >>>>> >>>>> org.apache.stratos.rest.endpoint.api.StratosApiV41Utils.addGroupsInstancesToApplicationInstanceBean(StratosApiV41Utils.java:979) >>>>> >>>>> org.apache.stratos.rest.endpoint.api.StratosApiV41Utils.getApplicationRuntime(StratosApiV41Utils.java:963) >>>>> >>>>> org.apache.stratos.rest.endpoint.api.StratosApiV41.getApplicationRuntime(StratosApiV41.java:579) >>>>> >>>>> Thanks >>>>> >>>>> >>>>> -- >>>>> Imesh Gunaratne >>>>> >>>>> Technical Lead, WSO2 >>>>> Committer & PMC Member, Apache Stratos >>>>> >>>> >>>> >>>> >>>> -- >>>> Imesh Gunaratne >>>> >>>> Technical Lead, WSO2 >>>> Committer & PMC Member, Apache Stratos >>>> >>> >>> >>> >>> -- >>> Imesh Gunaratne >>> >>> Technical Lead, WSO2 >>> Committer & PMC Member, Apache Stratos >>> >> >> > > > -- > Reka Thirunavukkarasu > Senior Software Engineer, > WSO2, Inc.:http://wso2.com, > Mobile: +94776442007 > > >
