[jira] [Commented] (CASSANDRA-6648) Race condition during node bootstrapping

["Brandon Williams (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-6648?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13890618#comment-13890618 ] 

Brandon Williams commented on CASSANDRA-6648:
---------------------------------------------

How many keyspaces/CFs are defined when this occurs?

> Race condition during node bootstrapping
> ----------------------------------------
>
>                 Key: CASSANDRA-6648
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-6648
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>            Reporter: Sergio Bossa
>            Priority: Critical
>
> When bootstrapping a new node, data is "missing" as if the new node didn't actually bootstrap, which I tracked down to the following scenario:
> 1) New node joins token ring and waits for schema to be settled before actually bootstrapping.
> 2) The schema scheck somewhat passes and it starts bootstrapping.
> 3) Bootstrapping doesn't find the ks/cf that should have received from the other node.
> 4) Queries at this point cause NPEs, until when later they "recover" but data is missed.
> The problem seems to be caused by a race condition between the migration manager and the bootstrapper, with the former running after the latter.
> I think this is supposed to protect against such scenarios:
> {noformat}
>             while (!MigrationManager.isReadyForBootstrap())
>             {
>                 setMode(Mode.JOINING, "waiting for schema information to complete", true);
>                 Uninterruptibles.sleepUninterruptibly(1, TimeUnit.SECONDS);
>             }
> {noformat}
> But MigrationManager.isReadyForBootstrap() implementation is quite fragile and doesn't take into account "slow" schema propagation.



--
This message was sent by Atlassian JIRA
(v6.1.5#6160)