[
https://issues.apache.org/jira/browse/OAK-7234?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16709730#comment-16709730
]
Michael Dürig commented on OAK-7234:
------------------------------------
{quote}My biggest concern about this issue is how we frame the problem.
{quote}
Agreed. I think it's safe to use the timestamp of the latest journal entry on
one hand. But what to compare it against? We'd need some way to determine a
timestamp from when the repository shut down the last time. In my patch I use
the timestamp of the most recent tar file. But I'm really not sure whether this
is a good heuristic.
So far I only know of a few cases where we had to deal with an outdated
journal. So any heuristic which has a higher false positive rate than that
would effectively make matters worse.
One other thing I could think of: run the journal recovery tool and let it
recover a few minutes worth of revisions. If non of those match the head
revision in the journal then log an error and refuse to start.
> Check for outdated journal at startup
> -------------------------------------
>
> Key: OAK-7234
> URL: https://issues.apache.org/jira/browse/OAK-7234
> Project: Jackrabbit Oak
> Issue Type: Improvement
> Components: segment-tar
> Reporter: Michael Dürig
> Assignee: Michael Dürig
> Priority: Minor
> Labels: resilience, tooling
> Fix For: 1.10
>
>
> To prevent accidentally branching the repository when the {{journal.log}}
> became outdated (e.g. OAK-3702) we could add an additional safety feature
> which would prevent the repository from starting in such cases. There's a
> couple of concerns to address:
> * What kind of tooling / guidance do we need to provide to recover should
> such a situation be detected?
> * How do we detect the {{journal.log}} being outdated?
> * How do we prevent false positives?
> * How do we deal with situation where the {{journal.log}} modifications are
> intended (e.g. by tools, of manual interventions)?
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
