[
https://issues.apache.org/jira/browse/OAK-585?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13566315#comment-13566315
]
Mete Atamel commented on OAK-585:
---------------------------------
One other point about CommitCommand. Currently, it has a needsRetry method that
determines what exceptions should trigger a retry and also numberOfRetries to
limit the number of retries. needsRetry makes sense because some exceptions
(eg. child already exists) should fail right away whereas some exceptions (eg.
concurrent updates) should cause retry. However, I feel like numberOfRetries
does not really work and not needed. If there are concurrent updates for
example, what's the right number of retries to try? Currently, this is set to
100 but it's arbitrary and if 100 runs out, what should the client do? I think
retry should happen as long as commit succeeds or another unretriable exception
is encountered.
> Reduce cost of commit retry
> ---------------------------
>
> Key: OAK-585
> URL: https://issues.apache.org/jira/browse/OAK-585
> Project: Jackrabbit Oak
> Issue Type: Improvement
> Components: mongomk
> Affects Versions: 0.6
> Reporter: Marcel Reutegger
> Attachments: OAK-585-1&2.patch, OAK-585-1&2.patch, OAK-585-1.patch,
> OAK-585-2.patch, OAK-585-3.patch
>
>
> MongoMK currently has a retry mechanism when it commits changes. Its main
> purpose is to make sure the headRevId in the sync collection is updated
> consistently and concurrent conflicting commits are detected. Under higher
> concurrency it may happen that commits are retried multiple times, even when
> commits are non-conflicting. In this case its only about consistently
> updating the headRevId. When this happens the commit will get a new revision
> and the nodes of the commit are written again with the new revision, even
> though no changes to the nodes are needed. Only the revision needed an update.
> The cost of a retry should be reduced in this case. At least a commit retry
> should not leave garbage in the nodes and commits collections.
--
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
