[ https://issues.apache.org/jira/browse/KUDU-3453?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Alexey Serbin updated KUDU-3453: -------------------------------- Summary: Fine-grained anchoring for WAL segments for tablet copy (was: Fine-grained anchoring for WAL segments during tablet copying) > Fine-grained anchoring for WAL segments for tablet copy > ------------------------------------------------------- > > Key: KUDU-3453 > URL: https://issues.apache.org/jira/browse/KUDU-3453 > Project: Kudu > Issue Type: Improvement > Components: tablet, tserver > Reporter: Alexey Serbin > Priority: Major > > Tablet copying is a provision to implement the process of automatic tablet > re-replication in Kudu. When the system catalog (Kudu master) detects that a > tablet replica is no longer available, it automatically re-replicates a > tablet to a destination tablet server using another healthy tablet replica in > the cluster as the source. > When copying a tablet from one tablet server to another, the source tablet > copying session "anchors" WAL segments to be transfered to the destination > server, so they are not GC-ed by the tablet maintenance operation when they > are no longer needed locally, but the tablet copy session is still in > progress. > The anchored WAL segments are releases all at once when the tablet copying > session completes with success of failure. However, there might be long > running tablet copying sessions, and with high data ingest rate, the source > tablet replica might accumulate huge amount of WAL data which isn't relevant > at both the source and the destination server. > To prevent accumulation of WAL data for long-running tablet copying sessions, > it's necessary to update the WAL anchors in a more granular manner, e.g. > un-anchor a segment once it has been successfully copied and persisted by the > client tablet copying session. -- This message was sent by Atlassian Jira (v8.20.10#820010)