> On July 20, 2014, 11:32 p.m., Jun Rao wrote: > > clients/src/main/java/org/apache/kafka/clients/NetworkClient.java, lines > > 376-377 > > <https://reviews.apache.org/r/23697/diff/1/?file=635933#file635933line376> > > > > Thinking a bit more about this. There are two possibility after adding > > the metadata request to sends: (1) The metadata fetch succeeds. In this > > case Metadata.lastRefreshMs will be updated and this line is not needed. > > (2) The metadata fetch fails due to a connection issue. In this case, we > > probably want to fetch the metadata request from another node immediately, > > instead of backing off. > > > > So, it seems that in NetworkClient, we only need to take care of the > > case when no node is available for metadata. In this case, we should > > backoff. So, perhaps we should rename metadataLastUpdateAttemptMs to sth > > like lastNoNodeMs.
Actually for the second case, the metadata fetch can fail either the selected node is not connected any more or it cannot accept any more requests (i.e. inFlightRequests.canSendMore() == false). In the latter case, since this node is selected as least loaded, there will be no other connected nodes that is available for sending also, and hence we should also back off. - Guozhang ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/23697/#review48194 ----------------------------------------------------------- On July 18, 2014, 10:45 p.m., Guozhang Wang wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/23697/ > ----------------------------------------------------------- > > (Updated July 18, 2014, 10:45 p.m.) > > > Review request for kafka. > > > Bugs: KAFKA-1533 > https://issues.apache.org/jira/browse/KAFKA-1533 > > > Repository: kafka > > > Description > ------- > > 1. Add the metadataRefreshAttemptMs in NetworkClient for backing off; 2. > Refactor Producer API tests using KafkaTestHarness; 3. Change default backoff > time to 100ms for test utils > > > Diffs > ----- > > clients/src/main/java/org/apache/kafka/clients/NetworkClient.java > d8f9ce663ee24d2b0852c974136741280c39f8f8 > > clients/src/main/java/org/apache/kafka/clients/producer/internals/Metadata.java > 4aa5b01d611631db72df47d50bbe30edb8c478db > core/src/test/scala/integration/kafka/api/ProducerFailureHandlingTest.scala > 15fd5bcbaf175a0f7d7cf0b142e63f705ca9b6ae > core/src/test/scala/integration/kafka/api/ProducerSendTest.scala > 34a7db4b4ea2b720476c2b1f22a623a997faffbc > core/src/test/scala/unit/kafka/integration/KafkaServerTestHarness.scala > 194dd70919a5f301d3131c56594e40a0ebb27311 > core/src/test/scala/unit/kafka/utils/TestUtils.scala > 3faa884f8eb83c7c00baab416d0acfb488dc39c1 > > Diff: https://reviews.apache.org/r/23697/diff/ > > > Testing > ------- > > > Thanks, > > Guozhang Wang > >
