[
https://issues.apache.org/jira/browse/OAK-7922?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Davide Giannella updated OAK-7922:
----------------------------------
Fix Version/s: 1.14.0
> Improve the operations and the reporting of the check command
> -------------------------------------------------------------
>
> Key: OAK-7922
> URL: https://issues.apache.org/jira/browse/OAK-7922
> Project: Jackrabbit Oak
> Issue Type: Improvement
> Components: segment-tar
> Reporter: Francesco Mari
> Assignee: Francesco Mari
> Priority: Major
> Fix For: 1.12.0, 1.14.0
>
> Attachments: OAK-7922-01.patch
>
>
> The check command allows a user to check for both the head and the
> checkpoints. At the end of the execution the command outputs the consistent
> revisions for the head and the individual checkpoints, if any is found.
> Moreover, it prints an overall good revision. The consistent revisions for
> the head and the checkpoints could all be different. If both the head and all
> the checkpoints are assigned to a consistent revision, the overall good
> revision is the oldest of those revisions.
> I wonder how useful all of this information is to a user of the command:
> - I might have a revision where a checkpoint is consistent, but the head is
> not. In this case, I don't want to revert to that revision because my system
> will probably be unstable due to the inconsistent head.
> - The overall good revision might still be partially inconsistent due to the
> way the command short-circuits the consistency check on the head and the
> checkpoints. If I revert to the overall good revision, the head might still
> be inconsistent or one of the checkpoints might be missing.
> I propose to remove the {{\--checkpoints}} and the {{\--head}} flags and
> define the behaviour of the command as follows.
> - The check command checks one super-root at a time in its entirety (both
> head and referenced checkpoints).
> - The command exits as soon as a super-root is found where both the head and
> all the checkpoints are consistent.
> - While searching, the command might find a super-root with a consistent
> head but one or more inconsistent checkpoint. In this case, the first of such
> revisions is printed, specifying which checkpoints are inconsistent.
> - The user might specify a {{--no-checkpoints}} flag to skip checking the
> checkpoints in the steps above.
> The optimisations currently implemented by the check command can be
> maintained. We don't need to fully traverse the head or the checkpoints if a
> well-known corrupted path is still corrupted in the current iteration. The
> approach proposed above enables additional optimisations:
> - Since checkpoints are immutable, the command doesn't need to traverse a
> checkpoint that was inspected before. This is true regardless of the
> consistency of the checkpoint.
> - If a super-root includes a checkpoint that was previously determined
> corrupted, the command can skip that super-root without further inspection.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
