hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "stack (Commented) (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-5270) Handle potential data loss due to concurrent processing of processFaileOver and ServerShutdownHandler
Date Wed, 29 Feb 2012 19:19:58 GMT

    [ https://issues.apache.org/jira/browse/HBASE-5270?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13219428#comment-13219428

stack commented on HBASE-5270:


bq. .... then the next step, that you outlined in your scenario, cannot be allowed

How should we do this boss?

bq. The problem you are outlining is probably still there but the scenario has to be refined.

What should I add?  If we allow that the split could take a long time, its possible that on
entry to the log splitting the server was good but by the end it could have gone AWOL.

bq. And then it should initialize everything based on that knowledge which must not change
during initialization.

I think the root issue is that it needs to scan .META. and -ROOT- as part of the startup;
they need to be assigned and up w/ all edits in place.  Thats whats proving to be a little
tough to ensure.

(Thanks for the review P).
> Handle potential data loss due to concurrent processing of processFaileOver and ServerShutdownHandler
> -----------------------------------------------------------------------------------------------------
>                 Key: HBASE-5270
>                 URL: https://issues.apache.org/jira/browse/HBASE-5270
>             Project: HBase
>          Issue Type: Sub-task
>          Components: master
>            Reporter: Zhihong Yu
>            Assignee: chunhui shen
>             Fix For: 0.92.1, 0.94.0
>         Attachments: 5270-90-testcase.patch, 5270-90-testcasev2.patch, 5270-90.patch,
5270-90v2.patch, 5270-90v3.patch, 5270-testcase.patch, 5270-testcasev2.patch, hbase-5270.patch,
hbase-5270v2.patch, hbase-5270v4.patch, hbase-5270v5.patch, hbase-5270v6.patch, hbase-5270v7.patch,
hbase-5270v8.patch, sampletest.txt
> This JIRA continues the effort from HBASE-5179. Starting with Stack's comments about
patches for 0.92 and TRUNK:
> Reviewing 0.92v17
> isDeadServerInProgress is a new public method in ServerManager but it does not seem to
be used anywhere.
> Does isDeadRootServerInProgress need to be public? Ditto for meta version.
> This method param names are not right 'definitiveRootServer'; what is meant by definitive?
Do they need this qualifier?
> Is there anything in place to stop us expiring a server twice if its carrying root and
> What is difference between asking assignment manager isCarryingRoot and this variable
that is passed in? Should be doc'd at least. Ditto for meta.
> I think I've asked for this a few times - onlineServers needs to be explained... either
in javadoc or in comment. This is the param passed into joinCluster. How does it arise? I
think I know but am unsure. God love the poor noob that comes awandering this code trying
to make sense of it all.
> It looks like we get the list by trawling zk for regionserver znodes that have not checked
in. Don't we do this operation earlier in master setup? Are we doing it again here?
> Though distributed split log is configured, we will do in master single process splitting
under some conditions with this patch. Its not explained in code why we would do this. Why
do we think master log splitting 'high priority' when it could very well be slower. Should
we only go this route if distributed splitting is not going on. Do we know if concurrent distributed
log splitting and master splitting works?
> Why would we have dead servers in progress here in master startup? Because a servershutdownhandler
> This patch is different to the patch for 0.90. Should go into trunk first with tests,
then 0.92. Should it be in this issue? This issue is really hard to follow now. Maybe this
issue is for 0.90.x and new issue for more work on this trunk patch?
> This patch needs to have the v18 differences applied.

This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira


View raw message