hbase-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "stack (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HBASE-533) Region Historian
Date Thu, 29 May 2008 14:48:45 GMT

    [ https://issues.apache.org/jira/browse/HBASE-533?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12600787#action_12600787

stack commented on HBASE-533:

On depth, are parent logs ending up in the daughter table entries or is it, IIRC, that you
create the page by doing selects first for daughter, then for parent, etc.?  If so, how about
putting parent logs in their own table below the current regions?  Set a static as you suggest
in the conf. for how many regions to list in the history page.

Regards event source, OK.   Add a bit of text to the end of the page that says this perhaps?

On split event, should include the address of parent region as well as name of parent region,
I'd suggest.

Sometimes compactions do nothing.  Perhaps we shouldn't log such events.  Might be hard to
do since compactions happen down in stores.

This morning I'm thinking that tying region history to log level setting might not be the
best idea but for the first version, its probably ok.  We can always change it after we get
this feature in.

> Region Historian
> ----------------
>                 Key: HBASE-533
>                 URL: https://issues.apache.org/jira/browse/HBASE-533
>             Project: Hadoop HBase
>          Issue Type: Wish
>            Reporter: Bryan Duxbury
>            Assignee: Jean-Daniel Cryans
>            Priority: Minor
>         Attachments: hbase-533-v1-fix.patch, hbase-533-v1.patch
> Whenever we try to debug region splitting, assignment, compaction, etc. issues, we always
end up having to look in 1-20 different log files for cryptic names of regions and try to
piece together the chain of events ourselves. This is a challenging at best effort most of
the time.
> What would be very useful would be a new utility I've nicknamed the Region Historian.
You give it the text name of a region, and it will track down the log messages relevant to
it in the master and regionserver logs. Then, it will interleave the messages in such a way
that the timestamps correctly list the order of events. The result is a log summary that accurately
describes what happened to a region during it's lifetime, making it much easier to try and
figure out where something went wrong.
> Other things it could do would be replace cryptic log messages with simple events like
"the region was split into a and b", "the region was assigned to server x", and trace the
lineage of a region backwards to its parent before it came into existence.
> I'm sure there are other things we would think up that would be useful as well.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

View raw message