[CASSANDRA-5699] Streaming (2.0) can deadlock

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 2.0 beta 1
• Severity: Normal
• Assignee: Sylvain Lebresne
• Reporter: Sylvain Lebresne

Authors

Sylvain Lebresne

Reviewers

Jonathan Ellis

• Created: 25/Jun/13 14:57
• Updated: 16/Apr/19 09:32
• Resolved: 03/Jul/13 17:56

Description

The new streaming implementation (CASSANDRA-5286) creates 2 threads per host for streaming, one for the incoming stream and one for the outgoing one. However, both currently share the same socket, but since we use synchronous I/O, a read can block a write, which can result in a deadlock if 2 nodes are both blocking on a read a the same time, thus blocking their respective writes (this is actually fairly easy to reproduce with a simple repair).

So instead attaching a patch that uses one socket per thread.

The patch also correct the stream throughput throttling calculation that was 8000 times lower than what it should be.