[ https://issues.apache.org/jira/browse/CASSANDRA-14930?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
ZhaoYang updated CASSANDRA-14930: --------------------------------- Description: On a 3-node cluster with RF=2, decommissioning a node may cause quorum write timeout because messaging backlog to decommissioned node is cleared via {{Gossiper#removeEndpoint() -> OutboundTcpConnection#closeSocket()}}. (Timeout is less likely to happen with RF=3, because we can afford one less response) {code:java} What happened: 1. [WriteStage] before the leaving node is removed from tokenmetadata, the write endpoints are generated ( leaving endpoint is included ) 2. [GossipStage] the leaving node is removed from tokenmetadata, no more future write handler will include leaving endpoints 3. [WriteStage] write handlers sends messages to messaging-service backlog 4. [GossipStage] messaging-service backlog is cleared, messages are not sent and connection closed 5. [WriteStage] write time out {code} | patch | | [3.0|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.0] | | [3.0|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.11] | We can avoid it by delaying to destroy messaging connection so that messages are sent and responded. This patch also avoids reopen already closed connection on {{MessagingService#convict()}}. New messaging framework rewrite in {{Trunk}} avoids the issues by not clearing messaging backlog. was: On a 3-node cluster with RF=2, decommissioning a node may cause quorum write timeout because messaging backlog to decommissioned node is cleared via {{Gossiper#removeEndpoint() -> OutboundTcpConnection#closeSocket()}}. (Timeout is less likely to happen with RF=3, because we can afford one less response) {code:java} What happened: 1. [WriteStage] before the leaving node is removed from tokenmetadata, the write endpoints are generated ( leaving endpoint is included ) 2. [GossipStage] the leaving node is removed from tokenmetadata, no more future write handler will include leaving endpoints 3. [WriteStage] write handlers sends messages to messaging-service backlog 4. [GossipStage] messaging-service backlog is cleared, messages are not sent and connection closed 5. [WriteStage] write time out {code} | patch | | [3.0|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.0] | | [3.0|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.11] | We can avoid it by delaying to destroy messaging connection so that messages are sent and responded. New messaging framework rewrite in {{Trunk}} avoids the issues by not clearing messaging backlog. > decommission may cause timeout because messaging backlog is cleared > -------------------------------------------------------------------- > > Key: CASSANDRA-14930 > URL: https://issues.apache.org/jira/browse/CASSANDRA-14930 > Project: Cassandra > Issue Type: Bug > Components: Coordination, Core > Reporter: ZhaoYang > Assignee: ZhaoYang > Priority: Major > Fix For: 3.0.x, 3.11.x > > > On a 3-node cluster with RF=2, decommissioning a node may cause quorum write > timeout because messaging backlog to decommissioned node is cleared via > {{Gossiper#removeEndpoint() -> OutboundTcpConnection#closeSocket()}}. > (Timeout is less likely to happen with RF=3, because we can afford one less > response) > {code:java} > What happened: > 1. [WriteStage] before the leaving node is removed from tokenmetadata, the > write endpoints are generated ( leaving endpoint is included ) > 2. [GossipStage] the leaving node is removed from tokenmetadata, no more > future write handler will include leaving endpoints > 3. [WriteStage] write handlers sends messages to messaging-service backlog > 4. [GossipStage] messaging-service backlog is cleared, messages are not sent > and connection closed > 5. [WriteStage] write time out > {code} > | patch | > | > [3.0|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.0] > | > | > [3.0|https://github.com/jasonstack/cassandra/commits/decommission_timeout_3.11] > | > We can avoid it by delaying to destroy messaging connection so that messages > are sent and responded. This patch also avoids reopen already closed > connection on {{MessagingService#convict()}}. > New messaging framework rewrite in {{Trunk}} avoids the issues by not > clearing messaging backlog. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org