[
https://issues.apache.org/jira/browse/HBASE-2437?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12871376#action_12871376
]
HBase Review Board commented on HBASE-2437:
-------------------------------------------
Message from: "Cosmin Lehene" <[email protected]>
Let's have a separate issue for that
done - for both reader and writer
done - both reader and writer impl
the original version of this function determined me to start refactoring in the
first place. I'll add the description but if it's still confusing it might need
more work.
I know and tried to get a better name when created it. Can you suggest
something better? I can't figure a short descriptive enough name
perhaps hbase.regionserver.hlog.splitlog.batch.size?
done
done
fixed
done
Fixed
done
done
sync() used to call syncFs(). It looks like HBASE-2544 changed things a bit,
but it doesn't only add the SequenceFile sync marker.
I added this after I've seen inconsistent results when running splitLog on
bigger hlogs. Try copying a log from the cluster locally and run splitLog from
the command line a few times without flushing it after each append. I used to
get inconsistent results between runs and calling sync fixed it.
There's this "//TODO: test the split of a large (lots of regions > 500 file).
In my tests it seems without hflush" in the TestHLogSplit.
We could do some testing to figure out why would log entries be lost when
running locally.
What would be a better way to flush the writer?
done
fixed
I don't know what it's supposed to mean either :)
fixed
I'd like to be able to investigate the trailing garbage. I don't think this
should ever happen (do you see any scenarios?). If it did we might lose data.
We used to fix NameNode edits for fsImage by adding a missing byte to a
corrupted entry.
I'd like to reflect more on this, maybe see other opinions.
I'd rather have these differences dealt at the lowest level (writers) and
abstracted than spread across code.
What do you think?
done
I'll need help setting guava as a maven dependency.
createNewSplitter is fine.
It's a Callable, changed to submit in order to check for the result in case one
of the writers failed (see comment below)
more aspects here:
I think the reported size will be >0 after recover, even if file has no
records. I was asking if we should add logic to check if it's the last log.
EOF for non zero length, non zero records file means file is corrupted.
see above comment
what's the other JIRA? see my above comments.
my previous comment got lost somehow.
Todd suggested submitting a Callable<Void> to executor thread.
I wonder if we could use getCompletedTaskCount. Documentation sais it's an
estimation, however it's an estimation only during runtime and seems to be
correct after shutdown finishes (I looked in the source as well)
Another option would be ExecutorCompletionService which seems to be suited for
this kind of job.
- Cosmin
-----------------------------------------------------------
This is an automatically generated e-mail. To reply, visit:
http://review.hbase.org/r/74/#review40
-----------------------------------------------------------
On 2010-05-21 12:11:59, stack wrote:
> Refactor HLog splitLog
> ----------------------
>
> Key: HBASE-2437
> URL: https://issues.apache.org/jira/browse/HBASE-2437
> Project: HBase
> Issue Type: Bug
> Components: master
> Affects Versions: 0.21.0
> Reporter: Cosmin Lehene
> Assignee: Cosmin Lehene
> Fix For: 0.21.0
>
> Attachments: 2437-v2.txt, 2437-v3.txt, 2437-v4.patch, 2437.txt,
> HBASE-2437_for_HBase-0.21_with_unit_tests_for_HDFS-0.21.patch
>
> Original Estimate: 120h
> Remaining Estimate: 120h
>
> the HLog.splitLog got really long and complex and hard to verify for
> correctness.
> I started to refactor it and also ported changes from hbase-2337 that deals
> with premature deletion of log files in case of errors. Further improvements
> will be possible, however the scope of this issue is to clean the code and
> make it behave correctly (i.e. not lose any edits)
> Added a suite of unit tests that might be ported to 0.20 as well.
> Added a setting (hbase.skip.errors - feel free to suggest a better name)
> that, when set to false will make the process less tolerant to failures or
> corrupted files: in case a log file is corrupted or an error stops the
> process from consistently splitting the log, will abort the entire operation
> to avoid losing any edits. When hbase.skip.errors is on any corrupted files
> will be partially parsed and then moved to the corrupted logs archive (see
> hbase-2337).
> Like hbase-2337 the splitLog method will first split all the logs and then
> proceed to archive them. If any splitted log file (oldlogfile.log) that is
> the result of an earlier splitLog attempt is found in the region directory,
> it will be deleted - this is safe since we won't move the original log files
> until the splitLog process completes.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
