Running out of PermGen space when using DeferredTasks in GAE 1.7.3

Question

I switched to Google App Engine Java SDK 1.7.3 recently. Since then, I am running out of PermGen space every time I am submitting DeferredTasks into the task queue.

• This does not happen when the app is deployed to App Engine. It only happens locally. But it is blocking my local testing and failing integration tests.

• It is happening on MacOSX 10.7.5 with Java 6

  $ java -version 
  java version "1.6.0_37"
  Java(TM) SE Runtime Environment (build 1.6.0_37-b06-434-11M3909)
  Java HotSpot(TM) 64-Bit Server VM (build 20.12-b01-434, mixed mode)
  

• And this is part of stacktrace I am seeing when the problem occurs.

  INFO: Successfully processed ../target/projectName/WEB-INF/queue.xml
  Nov 1, 2012 3:04:00 PM com.google.appengine.api.taskqueue.dev.LocalTaskQueue init
  INFO: LocalTaskQueue is initialized
  Nov 1, 2012 3:04:01 PM org.quartz.simpl.SimpleThreadPool initialize
  INFO: Job execution threads will use class loader of thread: 1255545583@qtp-1458850232-0
  Nov 1, 2012 3:04:02 PM org.quartz.core.QuartzScheduler <init>
  INFO: Quartz Scheduler v.UNKNOWN.UNKNOWN.UNKNOWN created.
  Nov 1, 2012 3:04:02 PM org.quartz.simpl.RAMJobStore initialize
  INFO: RAMJobStore initialized.
  Nov 1, 2012 3:04:02 PM org.quartz.impl.StdSchedulerFactory instantiate
  INFO: Quartz scheduler 'DefaultQuartzScheduler' initialized from default resource file in Quartz package: 'quartz.properties'
  Nov 1, 2012 3:04:02 PM org.quartz.impl.StdSchedulerFactory instantiate
  INFO: Quartz scheduler version: UNKNOWN.UNKNOWN.UNKNOWN
  Nov 1, 2012 3:04:02 PM org.quartz.core.QuartzScheduler start
  INFO: Scheduler DefaultQuartzScheduler_$_NON_CLUSTERED started.
  Nov 1, 2012 3:04:02 PM com.google.appengine.api.taskqueue.dev.LocalTaskQueue start_
  INFO: Local task queue initialized with base url http://localhost:8083
  Exception in thread "DefaultQuartzScheduler_Worker-9" java.lang.OutOfMemoryError: PermGen space
          at java.lang.ClassLoader.defineClass1(Native Method)
          at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
          at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
          at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
          at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
          at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
          at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
          at java.security.AccessController.doPrivileged(Native Method)
          at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
          at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
          at com.google.appengine.tools.development.DevAppServerClassLoader.loadClass(DevAppServerClassLoader.java:92)
          at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
          at com.google.appengine.api.urlfetch.URLFetchServicePb$URLFetchRequest.newBuilder(URLFetchServicePb.java:1902)
          at com.google.appengine.api.taskqueue.dev.UrlFetchJob.newFetchRequest(UrlFetchJob.java:152)
          at com.google.appengine.api.taskqueue.dev.UrlFetchJob.execute(UrlFetchJob.java:83)
          at org.quartz.core.JobRunShell.run(JobRunShell.java:203)
          at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)
  Exception in thread "1255545583@qtp-1458850232-0" java.lang.OutOfMemoryError: PermGen space
  Exception in thread "Timer-6" java.lang.OutOfMemoryError: PermGen space
  Exception in thread "Timer-4" java.lang.OutOfMemoryError: PermGen space
  Exception in thread "Timer-2" java.lang.OutOfMemoryError: PermGen space
  Exception in thread "Timer-8" java.lang.OutOfMemoryError: PermGen space
  

See below for the code that triggers the issue. The DeferredTask has a memcache reference to get data from memcache and potentially remove it. The task is running with a delay of 10 seconds.

class Foo {
    private void enqueueTask() {
        queue.add(TaskOptions.Builder.withPayload(new Task()).countdownMillis(10 * 1000));
    }

    private static class Task implements DeferredTask {
        private static final MemcacheService memcache = MemcacheServiceFactory.getMemcacheService();
        private static final Logger log = Logger.getLogger(Task.class.getName());

        @Override
        public void run() {
            final String key = ...;

            if (memcache.contains(key)) {
                final Object value = memcache.get(key);

                if (some condition depending on value) {
                    memcache.delete(key);
                    memcache.increment(some other field, -1l);
                }
            } else {
                log.warning("error message");
            }
        }
    }
}

Can somebody else reproduce this? Thanks!

Update: I created issue 8377 for this on the GAE's Google Code page.

Answer 1

This isssue was resolved Aug 12, 2014 in the 1.9.6 AppEngine SDK release. MaxPermSize can only be set on the local dev server.