[
https://issues.apache.org/activemq/browse/CAMEL-3348?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=63455#action_63455
]
Claus Ibsen commented on CAMEL-3348:
------------------------------------
Yeah there is maybe this problem but its much less likely to happen.
Let me try to register the task pre emptive before polling. Then we use a bit
more logic to figure out if we shutting down and wait until all pending
exchanges and tasks has been completed.
The problem with the executor service if you use {{shutdownNow}} is that it
will maybe also interrupt and stop currently processed exchanges.
And all we just want to do is to stop the threads which is doing poll. But we
can't do that easily, hence we gotta figure this out differently.
> DefaultShutdownStrategy and ShutdownAware (SedaConsumer) losing exchange
> ------------------------------------------------------------------------
>
> Key: CAMEL-3348
> URL: https://issues.apache.org/activemq/browse/CAMEL-3348
> Project: Apache Camel
> Issue Type: Bug
> Components: camel-core
> Affects Versions: 2.5.0
> Reporter: Damien Delautre
> Assignee: Claus Ibsen
> Fix For: 2.6.0
>
>
> There's a problem when we shutdown the camel context with a seda endpoint.
> In the SedaConsumer, the exchange is removed from the queue and then, later,
> is added to the InflightRepository as shown in the following code (I put
> comments where it is done):
> {code}
> public void run() {
> BlockingQueue<Exchange> queue = endpoint.getQueue();
> while (queue != null && isRunAllowed()) {
> final Exchange exchange;
> try {
> exchange = queue.poll(1000, TimeUnit.MILLISECONDS); // The
> exchange is removed here from the queue
> } catch (InterruptedException e) {
> if (LOG.isDebugEnabled()) {
> LOG.debug("Sleep interrupted, are we stopping? " +
> (isStopping() || isStopped()));
> }
> continue;
> }
> if (exchange != null) {
> if (isRunAllowed()) {
> try {
> sendToConsumers(exchange); // Call to sendToConsumers
> detailed below
> if (exchange.getException() != null) {
> getExceptionHandler().handleException("Error
> processing exchange", exchange, exchange.getException());
> }
> } catch (Exception e) {
> getExceptionHandler().handleException("Error
> processing exchange", exchange, e);
> }
> } else {
> if (LOG.isWarnEnabled()) {
> LOG.warn("This consumer is stopped during polling an
> exchange, so putting it back on the seda queue: " + exchange);
> }
> try {
> queue.put(exchange);
> } catch (InterruptedException e) {
> if (LOG.isDebugEnabled()) {
> LOG.debug("Sleep interrupted, are we stopping? "
> + (isStopping() || isStopped()));
> }
> continue;
> }
> }
> }
> }
> }
> protected void sendToConsumers(Exchange exchange) throws Exception {
> int size = endpoint.getConsumers().size();
> if (size > 1) {
> if (LOG.isDebugEnabled()) {
> LOG.debug("Multicasting to " + endpoint.getConsumers().size()
> + " consumers for Exchange: " + exchange);
> }
>
> MulticastProcessor mp = endpoint.getConumserMulticastProcessor();
> AsyncProcessorHelper.process(mp, exchange, new AsyncCallback() {
> public void done(boolean doneSync) {
> }
> });
> } else {
> AsyncProcessorHelper.process(processor, exchange, new
> AsyncCallback() { // This line will create the UnitOfWork (in
> UnitOfWorkProcessor) which will put the exchange in the InflightRepository
> public void done(boolean doneSync) {
> }
> });
> }
> }
> {code}
> If the shutdown occurs between these two actions, the DefaultShutdownStrategy
> will shutdown the route even if there is a message in progress. And the
> message will be lost.
> Here is the code of ShutdownTask in DefaultShutdownStrategy which cause the
> shutdown even if there is some messages still in progress. (I put comments in
> it to show the state of the seda queue and InflightRepository if it is called
> between the queue.poll() and the InflightRepository.add())
> {code}
> for (Consumer consumer : order.getInputs()) {
> int inflight =
> context.getInflightRepository().size(consumer.getEndpoint()); // check the
> number of inflight exchanges which is 0 because the UnitOfWork is not created
> if (consumer instanceof ShutdownAware) {
> inflight += ((ShutdownAware)
> consumer).getPendingExchangesSize(); // check the number of exchange in the
> seda queue which is 0 because the message is already removed
> }
> if (inflight > 0) {
> size += inflight;
> if (LOG.isDebugEnabled()) {
> LOG.debug(inflight + " inflight and pending
> exchanges for consumer: " + consumer);
> }
> }
> }
> {code}
> You can reproduce it by putting a breakpoint in the method {code}protected
> void sendToConsumers(Exchange exchange){code} in SedaConsumer and calling
> stop() on the CamelContext while the thread is suspended by the breakpoint.
> We caught the problem in a unit test where we were testing the shutdown and
> when our test server was under heavy load.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
