I want to make sure that the following logic in EnableTableHandler is
correct:
(1). In EnableTableHandler#prepare - if the table is not existed, it marked
the table as deleted and not throw exception. The result is the table lock
is released and the caller has no knowledge that the table not exist or
already deleted, it would continue the next step.
Currently, this would happen during recovery (the caller is
AssignmentManager#recoverTableInEnablingState()) - however, looking at
recovery code, it expects TableNotFoundException Should we always throw
exception - if the table not exist? I want to make sure that I don't break
recovery logic by modifying.
public EnableTableHandler prepare() {
...
// Check if table exists
if (!MetaTableAccessor.tableExists(this.server.getConnection(),
tableName)) {
// retainAssignment is true only during recovery. In normal case
it is false
if (!this.skipTableStateCheck) {
throw new TableNotFoundException(tableName);
}
this.assignmentManager.getTableStateManager().setDeletedTable(
tableName);
}
...
}
(2). In EnableTableHandler#handleEnableTable() - if the bulk assign plan
could not be find, it would leave regions to be offline and declare enable
table succeed - i think this is a bug and we should retry or fail - but I
want to make sure that there are some merit behind this logic
private void handleEnableTable() {
Map<ServerName, List<HRegionInfo>> bulkPlan =
this.assignmentManager.getBalancer().retainAssignment(
regionsToAssign, onlineServers);
if (bulkPlan != null) {
...
} else {
LOG.info("Balancer was unable to find suitable servers for table " +
tableName
+ ", leaving unassigned");
done = true;
}
if (done) {
// Flip the table to enabled.
this.assignmentManager.getTableStateManager().setTableState(
this.tableName, TableState.State.ENABLED);
LOG.info("Table '" + this.tableName
+ "' was successfully enabled. Status: done=" + done);
}
...
}
thanks
Stephen
