[
https://issues.apache.org/jira/browse/KUDU-2083?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16118544#comment-16118544
]
Matthew Jacobs commented on KUDU-2083:
--------------------------------------
This was seen in an Impala test job: IMPALA-5770
> MaintenanceManager running_op_ count not decremented if
> MaintenanceOp::Prepare() fails
> --------------------------------------------------------------------------------------
>
> Key: KUDU-2083
> URL: https://issues.apache.org/jira/browse/KUDU-2083
> Project: Kudu
> Issue Type: Bug
> Reporter: Samuel Okrent
> Priority: Minor
>
> In MaintenanceManager::RunSchedulerThread(), an op gets selected,
> running_ops_ is incremented, and Prepare() is called on the op. If Prepare()
> returns false, the op isn't run, so running_ops_ never gets decremented. If
> Prepare() ever fails, then this could be a problem, as the maintenance
> manager compares running_ops_ to the number of operation threads to determine
> whether or not it can run another operation. Prepare generally doesn't fail,
> but if Tablet::AlterSchema() is called in between FlushMRSOp::UpdateStats()
> and FlushMRSOp::Prepare(), that is one instance where Prepare() could
> potentially fail.
> To fix, decrement running_ops_ in the codepath that follows from Prepare()
> failing.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
