[
https://issues.apache.org/jira/browse/HDFS-11412?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Manoj Govindassamy updated HDFS-11412:
--------------------------------------
Status: Patch Available (was: Open)
> Maintenance minimum replication config value allowable range should be {0 -
> DefaultReplication}
> -----------------------------------------------------------------------------------------------
>
> Key: HDFS-11412
> URL: https://issues.apache.org/jira/browse/HDFS-11412
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Components: datanode, namenode
> Affects Versions: 3.0.0-alpha1
> Reporter: Manoj Govindassamy
> Assignee: Manoj Govindassamy
> Attachments: HDFS-11412.01.patch
>
>
> Currently the allowed value range for Maintenance Min Replication
> {{dfs.namenode.maintenance.replication.min}} is 0 to
> {{dfs.namenode.replication.min}} (default=1). Users wanting not to affect the
> performance of the cluster would wish to have the Maintenance Min Replication
> number greater than 1, say 2. In the current design, it is possible to have
> this Maintenance Min Replication configuration, but only after changing the
> NameNode level Block Min Replication to 2, and which could slowdown the
> overall latency for client writes.
> Technically speaking we should be allowing Maintenance Min Replication to be
> in range 0 to dfs.replication.max.
> * There is always config value of 0 for users not wanting any
> availability/performance during maintenance.
> * And, performance centric workloads can still get maintenance done without
> major disruptions by having a bigger Maintenance Min Replication. Setting the
> upper limit as dfs.replication.max could be an overkill as it could trigger
> re-replication which Maintenance State is trying to avoid. So, we could allow
> the {{dfs.namenode.maintenance.replication.min}} in the range {{0 to
> dfs.replication}}
> {noformat}
> if (minMaintenanceR < 0) {
> throw new IOException("Unexpected configuration parameters: "
> + DFSConfigKeys.DFS_NAMENODE_MAINTENANCE_REPLICATION_MIN_KEY
> + " = " + minMaintenanceR + " < 0");
> }
> if (minMaintenanceR > minR) {
> throw new IOException("Unexpected configuration parameters: "
> + DFSConfigKeys.DFS_NAMENODE_MAINTENANCE_REPLICATION_MIN_KEY
> + " = " + minMaintenanceR + " > "
> + DFSConfigKeys.DFS_NAMENODE_REPLICATION_MIN_KEY
> + " = " + minR);
> {noformat}
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)
---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org
