From
activemq/activemq-core/src/main/java/org/apache/activemq/store/journal/JournalPersistenceAdapterFactory.java
private int journalLogFileSize = 1024 * 1024 * 20;
private int journalLogFiles = 2;
In
activemq/activemq-core/src/main/java/org/apache/activemq/store/journal/JournalPersistenceAdapter.java
private final long checkpointInterval = 1000 * 60 * 5;
private long lastCheckpointRequest = System.currentTimeMillis();
private long lastCleanup = System.currentTimeMillis();
private int maxCheckpointWorkers = 10;
private int maxCheckpointMessageAddSize = 1024 * 1024;
public synchronized void start() throws Exception {
if (!started.compareAndSet(false, true)) {
return;
}
checkpointTask = taskRunnerFactory.createTaskRunner(new Task() {
public boolean iterate() {
return doCheckpoint();
}
}, "ActiveMQ Journal Checkpoint Worker");
checkpointExecutor = new ThreadPoolExecutor(maxCheckpointWorkers,
maxCheckpointWorkers, 30, TimeUnit.SECONDS, new
LinkedBlockingQueue<Runnable>(), new ThreadFactory() {
public Thread newThread(Runnable runable) {
Thread t = new Thread(runable, "Journal checkpoint worker");
t.setPriority(7);
return t;
}
});
// checkpointExecutor.allowCoreThreadTimeOut(true);
this.usageManager.getMemoryUsage().addUsageListener(this);
if (longTermPersistence instanceof JDBCPersistenceAdapter) {
// Disabled periodic clean up as it deadlocks with the checkpoint
// operations.
((JDBCPersistenceAdapter)longTermPersistence).setCleanupPeriod(0);
}
longTermPersistence.start();
createTransactionStore();
recover();
// Do a checkpoint periodically.
this.scheduler = new Scheduler("Journal Scheduler");
this.scheduler.start();
this.scheduler.executePeriodically(periodicCheckpointTask,
checkpointInterval / 10);
}
On Oct 22, 2010, at 5:29 PM, kseelam wrote:
>
> Hi,
>
> We are looking at using High performance journal with JDBC as described at
> http://activemq.apache.org/persistence.html
>
> It mentioned that only outstanding messages will be persisted in the DB (by
> batch) when the checkpoint tot he DB happens.
>
> Could anyone explain how exactly the 'checkpoint' works? I did not find any
> checkpointInterval attribute.
> Also how the journalLogFiles and journalLogFileSize work?
>
> We are looking at some design/architectural point of view and any reference
> to any of the document would be highly appreciated.
>
> Thank you all.
> Krishna
>
>
>
> --
> View this message in context:
> http://activemq.2283324.n4.nabble.com/Checkpoint-on-High-performance-journal-tp3008012p3008012.html
> Sent from the ActiveMQ - Dev mailing list archive at Nabble.com.
Johan Edstrom
[email protected]
They that can give up essential liberty to purchase a little temporary safety,
deserve neither liberty nor safety.
Benjamin Franklin, Historical Review of Pennsylvania, 1759
