The Aerospike Knowledge Base has moved to https://support.aerospike.com. Content on https://discuss.aerospike.com is being migrated to either https://support.aerospike.com or https://docs.aerospike.com. Maintenance on articles stored in this repository ceased on December 31st 2022 and this article may be stale. If you have any questions, please do not hesitate to raise a case via https://support.aerospike.com.
FAQ Why are migration messages shown even when migrate-fill-delay is set
Detail
A cluster has a non-zero value set for migrate-fill-delay however in the event of a node removal the aerospike.log shows partitions to be migrated as follows:
Jun 04 2019 13:56:01 GMT: INFO (partition): (partition_balance.c:957) {migrate-test} rebalanced: expected-migrations (1340,1389,1340) fresh-partitions 0
Why are these messages shown?
Answer
The answer lies in the two part mechanism by which an Aerospike cluster will rebalance after a cluster event.
-
The first part of that is the cluster determines which partitions should go to which nodes in the new cluster state.
-
The second part of the process is the movement of partitions between nodes to reflect the partition mapping decision.
When migrate-fill-delay is set to a non-zero value it inserts the specified delay between these two steps. The cluster decides where the partitions will go and then waits for migrate-fill-delay until it actually moves the data.
This will be reflected in a subsequent log line as follows:
Jun 04 2019 13:56:04 GMT: INFO (info): (ticker.c:454) {test} migrations: remaining (1340,1389,1340) active (0,0,0) complete-pct 0.00
The line is stating that there are pending migrations but that there are none active as the migrations have been delayed.
The product is working as designed.
Keywords
MIGRATE FILL DELAY MIGRATIONS ACTIVE
Timestamp
June 17 2019