Reading Backtraces

Sarama uses a number of goroutines internally, so when golang dumps a stack trace (hopefully not because Sarama itself has crashed) this page provides a quick guide of what is safe to ignore.

Common

• [select]: github.com/IBM/sarama.(*client).backgroundMetadataUpdater is the background goroutine that wakes up every so often (controlled by Metadata.RefreshFrequency) and calls RefreshMetadata(). This can usually be ignored.

• [chan receive]: github.com/IBM/sarama.(*Broker).responseReceiver indicates a broker connection that is open, but not currently sending or receiving. These can usually be ignored, unless there are more of them than you have brokers.

Producer

• [chan receive]: github.com/IBM/sarama.(*asyncProducer).dispatcher is the producer's main goroutine waiting for the next message from the user
• [chan receive]: github.com/IBM/sarama.(*topicProducer).dispatch is a producer goroutine (one per topic being produced to) for partitioning messages
• [chan receive]: github.com/IBM/sarama.(*partitionProducer).dispatch is a producer goroutine (one per partition) for associating messages with the correct broker
• [select]: github.com/IBM/sarama.(*brokerProducer).run is a producer goroutine (one per broker) for collecting messages and constructing/sending produce requests
• [chan receive]: github.com/IBM/sarama.(*asyncProducer).retryHandler is a single producer goroutine which only wakes up to handle message retries

Consumer

• [chan receive]: github.com/IBM/sarama.(*partitionConsumer).dispatcher is a consumer goroutine (one per partition being consumed) which handles associating partitions with their brokers and is usually quiet
• [chan receive]: github.com/IBM/sarama.(*partitionConsumer).responseFeeder is a consumer goroutine (one per partition being consumed) which handles feeding messages to the user
• [select]: github.com/IBM/sarama.(*brokerConsumer).subscriptionManager is a consumer goroutine (one per broker) which manages subscriptions for consuming from individual partitions and is usually quiet
• [chan receive]: github.com/IBM/sarama.(*brokerConsumer).subscriptionConsumer is a consumer goroutine (one per broker) which actually sends fetch requests and handles the responses