[ https://issues.apache.org/jira/browse/HADOOP-11771?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Gopal V updated HADOOP-11771: ----------------------------- Description: {code} IPC Client (1970436060) connection to cn106-10.l42scl.hortonworks.com/172.21.128.106:34530 from application_1442254312093_2976 [BLOCKED] [DAEMON] org.apache.hadoop.conf.Configuration.getClassByNameOrNull(String) Configuration.java:2117 org.apache.hadoop.conf.Configuration.getClassByName(String) Configuration.java:2099 org.apache.hadoop.io.ObjectWritable.loadClass(Configuration, String) ObjectWritable.java:373 org.apache.hadoop.io.ObjectWritable.readObject(DataInput, ObjectWritable, Configuration) ObjectWritable.java:282 org.apache.hadoop.io.ObjectWritable.readFields(DataInput) ObjectWritable.java:77 org.apache.hadoop.ipc.Client$Connection.receiveRpcResponse() Client.java:1098 org.apache.hadoop.ipc.Client$Connection.run() Client.java:977 {code} {code} private static final Map<ClassLoader, Map<String, WeakReference<Class<?>>>> CACHE_CLASSES = new WeakHashMap<ClassLoader, Map<String, WeakReference<Class<?>>>>(); ... synchronized (CACHE_CLASSES) { map = CACHE_CLASSES.get(classLoader); if (map == null) { map = Collections.synchronizedMap( new WeakHashMap<String, WeakReference<Class<?>>>()); CACHE_CLASSES.put(classLoader, map); } } {code} !configuration-sync-cache.png! !configuration-cache-bt.png! was: {code} private static final Map<ClassLoader, Map<String, WeakReference<Class<?>>>> CACHE_CLASSES = new WeakHashMap<ClassLoader, Map<String, WeakReference<Class<?>>>>(); ... synchronized (CACHE_CLASSES) { map = CACHE_CLASSES.get(classLoader); if (map == null) { map = Collections.synchronizedMap( new WeakHashMap<String, WeakReference<Class<?>>>()); CACHE_CLASSES.put(classLoader, map); } } {code} !configuration-sync-cache.png! !configuration-cache-bt.png! > Configuration::getClassByNameOrNull synchronizes on a static object > ------------------------------------------------------------------- > > Key: HADOOP-11771 > URL: https://issues.apache.org/jira/browse/HADOOP-11771 > Project: Hadoop Common > Issue Type: Sub-task > Components: conf, io, ipc > Reporter: Gopal V > Priority: Critical > Attachments: configuration-cache-bt.png, configuration-sync-cache.png > > > {code} > IPC Client (1970436060) connection to > cn106-10.l42scl.hortonworks.com/172.21.128.106:34530 from > application_1442254312093_2976 [BLOCKED] [DAEMON] > org.apache.hadoop.conf.Configuration.getClassByNameOrNull(String) > Configuration.java:2117 > org.apache.hadoop.conf.Configuration.getClassByName(String) > Configuration.java:2099 > org.apache.hadoop.io.ObjectWritable.loadClass(Configuration, String) > ObjectWritable.java:373 > org.apache.hadoop.io.ObjectWritable.readObject(DataInput, ObjectWritable, > Configuration) ObjectWritable.java:282 > org.apache.hadoop.io.ObjectWritable.readFields(DataInput) > ObjectWritable.java:77 > org.apache.hadoop.ipc.Client$Connection.receiveRpcResponse() Client.java:1098 > org.apache.hadoop.ipc.Client$Connection.run() Client.java:977 > {code} > {code} > private static final Map<ClassLoader, Map<String, WeakReference<Class<?>>>> > CACHE_CLASSES = new WeakHashMap<ClassLoader, Map<String, > WeakReference<Class<?>>>>(); > ... > synchronized (CACHE_CLASSES) { > map = CACHE_CLASSES.get(classLoader); > if (map == null) { > map = Collections.synchronizedMap( > new WeakHashMap<String, WeakReference<Class<?>>>()); > CACHE_CLASSES.put(classLoader, map); > } > } > {code} > !configuration-sync-cache.png! > !configuration-cache-bt.png! -- This message was sent by Atlassian JIRA (v6.3.4#6332)