Workflow Show: use timeUpdated to calculate vreplication lag #7342
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…ove unused column MaxReplicationLag Signed-off-by: Rohit Nayak <rohit@planetscale.com>
Signed-off-by: Rohit Nayak <rohit@planetscale.com>
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Signed-off-by: Rohit Nayak rohit@planetscale.com
Description
There was a problem in the initial implementation of determining MaxVReplicationLag, which was the seconds since
transaction_timestamp. MaxVReplicationLag is used, in a Reshard workflow, by the operator to determine when resharding is completed. See VReplication stream heartbeats record incorrect event timestamps #6946, which logs the problem and fixes it. However this fix was problematic for two reasons:transaction_timestampis 0 as long as the stream is in the copy phase. If there are no new writes on the source once the copy phase is completed then the value does not get updatedtransaction_timestampcolumn for that stream does not get updated as there are no new events seen by the target.In both cases the operator decides that the stream is lagging and doesn't perform the cutover. This PR changes the logic to use the
time_updatedcolumn instead oftransaction_timestamp.time_updatedis updated both when there is a binlog event from the source and also when the source sends a heartbeat (every idle second).Don't display unused column
max_replication_lagfrom_vt.vreplicationThis column was used several versions earlier for throttling SplitClone streams. Vreplication workflows do not use it and it should not be displayed since it always displays MaxInt and is confusing to users.
Related Issue(s)
#6946
Checklist
Impacted Areas in Vitess
Components that this PR will affect: