[ https://issues.apache.org/jira/browse/SLING-5847?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Konrad Windszus updated SLING-5847: ----------------------------------- Summary: Deadlock in JcrResourceBundleProvider.getResourceBundleInternal when preloading is enabled (was: Deadlock in JcrResourceBundleProvider.getResourceBundleInternal) > Deadlock in JcrResourceBundleProvider.getResourceBundleInternal when > preloading is enabled > ------------------------------------------------------------------------------------------ > > Key: SLING-5847 > URL: https://issues.apache.org/jira/browse/SLING-5847 > Project: Sling > Issue Type: Bug > Components: Extensions > Affects Versions: i18n 2.4.4 > Reporter: Konrad Windszus > Assignee: Konrad Windszus > Priority: Critical > > Under particular timing situations the {{reloadBundle}} job and a parallel > call to {{JcrResourceBundleProvider.getResourceBundleInternal()}} might block > each other and also all new threads calling > {{JcrResourceBundleProvider.getResourceBundleInternal()}}. > The thread dump in that situation looks like follows > {code} > "0:0:0:0:0:0:0:1 [1468492407436] GET <some request url> HTTP/1.1" - Thread > t@69826 > java.lang.Thread.State: BLOCKED > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.registerResourceBundle(JcrResourceBundleProvider.java:458) > - waiting to lock <19c60354> (a > org.apache.sling.i18n.impl.JcrResourceBundleProvider) owned by > "pool-8-thread-5" t@111 > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.getResourceBundleInternal(JcrResourceBundleProvider.java:437) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.createResourceBundle(JcrResourceBundleProvider.java:480) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.getResourceBundleInternal(JcrResourceBundleProvider.java:435) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.getResourceBundle(JcrResourceBundleProvider.java:185) > at > org.apache.sling.i18n.impl.I18NFilter$CombinedBundleProvider.getResourceBundle(I18NFilter.java:217) > at > org.apache.sling.i18n.impl.I18NFilter$BaseI18NSlingHttpServletRequest.getResourceBundle(I18NFilter.java:311) > at > org.apache.sling.api.wrappers.SlingHttpServletRequestWrapper.getResourceBundle(SlingHttpServletRequestWrapper.java:115) > at > org.apache.sling.api.wrappers.SlingHttpServletRequestWrapper.getResourceBundle(SlingHttpServletRequestWrapper.java:115) > at > org.apache.sling.api.wrappers.SlingHttpServletRequestWrapper.getResourceBundle(SlingHttpServletRequestWrapper.java:115) > at > org.apache.sling.api.wrappers.SlingHttpServletRequestWrapper.getResourceBundle(SlingHttpServletRequestWrapper.java:115) > at > org.apache.sling.api.wrappers.SlingHttpServletRequestWrapper.getResourceBundle(SlingHttpServletRequestWrapper.java:115) > at ... > "pool-8-thread-5" - Thread t@111 > java.lang.Thread.State: WAITING > at sun.misc.Unsafe.park(Native Method) > - parking to wait for <69b06467> (a > java.util.concurrent.Semaphore$NonfairSync) > at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:997) > at > java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1304) > at java.util.concurrent.Semaphore.acquire(Semaphore.java:312) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.getResourceBundleInternal(JcrResourceBundleProvider.java:429) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.createResourceBundle(JcrResourceBundleProvider.java:480) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.getResourceBundleInternal(JcrResourceBundleProvider.java:435) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.getResourceBundle(JcrResourceBundleProvider.java:185) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.reloadBundle(JcrResourceBundleProvider.java:357) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider.reloadBundle(JcrResourceBundleProvider.java:352) > at > org.apache.sling.i18n.impl.JcrResourceBundleProvider$2.run(JcrResourceBundleProvider.java:320) > - locked <19c60354> (a > org.apache.sling.i18n.impl.JcrResourceBundleProvider) > at > org.apache.sling.commons.scheduler.impl.QuartzJobExecutor.execute(QuartzJobExecutor.java:115) > at org.quartz.core.JobRunShell.run(JobRunShell.java:202) > at > java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) > at > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) > at java.lang.Thread.run(Thread.java:745) > {code} > Here is what happens internally: > Thread 1 has acquired a semaphore for a specific key and now waits for the > lock hold by thread 2 in > {code} > private void registerResourceBundle(Key key, JcrResourceBundle > resourceBundle) { > Dictionary<Object, Object> serviceProps = new Hashtable<Object, > Object>(); > if (key.baseName != null) { > serviceProps.put("baseName", key.baseName); > } > serviceProps.put("locale", key.locale.toString()); > ServiceRegistration serviceReg = > bundleContext.registerService(ResourceBundle.class.getName(), > resourceBundle, serviceProps); > -> synchronized (this) { > bundleServiceRegistrations.put(key, serviceReg); > } > {code} > Thread 2 holds that lock in > {code} > private void scheduleReloadBundle(JcrResourceBundle bundle) { > String baseName = bundle.getBaseName(); > Locale locale = bundle.getLocale(); > final Key key = new Key(baseName, locale); > // defer this job > ScheduleOptions options = scheduler.AT(new > Date(System.currentTimeMillis() + invalidationDelay)); > final String jobName = "JcrResourceBundleProvider: reload bundle with > key " + key.toString(); > scheduledJobNames.add(jobName); > options.name(jobName); > scheduler.schedule(new Runnable() { > @Override > public void run() { > synchronized(JcrResourceBundleProvider.this) { > -> reloadBundle(key); > } > scheduledJobNames.remove(jobName); > } > }, options); > } > {code} > and now waits for the same semaphore that is being hold by thread 1. -- This message was sent by Atlassian JIRA (v6.3.4#6332)