hbase-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Gabriel Reid (JIRA)" <j...@apache.org>
Subject [jira] [Created] (HBASE-7634) Replication handling of changes to peer clusters is inefficient
Date Mon, 21 Jan 2013 16:04:12 GMT
Gabriel Reid created HBASE-7634:

             Summary: Replication handling of changes to peer clusters is inefficient
                 Key: HBASE-7634
                 URL: https://issues.apache.org/jira/browse/HBASE-7634
             Project: HBase
          Issue Type: Bug
          Components: Replication
    Affects Versions: 0.96.0
            Reporter: Gabriel Reid
         Attachments: HBASE-7634.patch

The current handling of changes to the region servers in a replication peer cluster is currently
quite inefficient. The list of region servers that are being replicated to is only updated
if there are a large number of issues encountered while replicating.

This can cause it to take quite a while to recognize that a number of the regionserver in
a peer cluster are no longer available. A potentially bigger problem is that if a replication
peer cluster is started with a small number of regionservers, and then more region servers
are added after replication has started, the additional region servers will never be used
for replication (unless there are failures on the in-use regionservers).

Part of the current issue is that the retry code in ReplicationSource#shipEdits checks a randomly-chosen
replication peer regionserver (in ReplicationSource#isSlaveDown) to see if it is up after
a replication write has failed on a different randonly-chosen replication peer. If the peer
is seen as not down, another randomly-chosen peer is used for writing.

A second part of the issue is that changes to the list of region servers in a peer cluster
are not detected at all, and are only picked up if a certain number of failures have occurred
when trying to ship edits.

This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

View raw message