[jira] [Commented] (HBASE-5583) Master restart on create table with splitkeys does not recreate table with all the splitkey regions

["ramkrishna.s.vasudevan (Commented) (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HBASE-5583?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13245371#comment-13245371 ] 

ramkrishna.s.vasudevan commented on HBASE-5583:
-----------------------------------------------

First step update the status in the below to CREATETABLE
/hbase/table/tableName
/hbase/table/tableName/currentstep



-> Create nodes with hregioninfo in the constructor of create table handler.
Create those many nodes as in the splitkeys.


-> /hbase/table/tableName/currentStep
CREATED_SPLIT_KEYS (after the creation of all splitkey nodes)
CREATING_TD
ADD_TO_META
ASSIGN_USER_REGIONS

if all are done 'ENABLED' will be the state of the table.

-> add regioninfo to  META and on success delete the node created node one by one



-> IF master fail over happens

See in what step the node is
============================

If failed in ASSIGN_USER_REGIONS 
Just reassign all the regions

If failed in ADD_TO_META
Check what regions are not yet added to meta and then do the assignment for all the regions
We can ensure that the nodes that are available in the zk are the ones for which the meta entry is not updated

If failed in CREATING_TD
If tabledescriptor not found create it again. if not go to the next step

If failed in CREATED_SPLIT_KEYS
Delete the node so that atleast the next time creation is successful.  Just log it as we cannot throw error back to the client.

===================================================================================

We need to create one more api in client called 'isTableAvailable()' accepting  splitKeys also.  so that the user can use them to check if really 
the table is created with all the splitkeys.
Currently the isTableAvailable() just checks if atleast one region is assigned to any RS.

The current changes does not guarentee that the user table will be created in a synchronous way to the client createTable api.
but will ensure that while creating any table if the master failover happens the table doesnot get created with less number of
regions but still the user thinks table creation is sucessful.

We now distinguish the states where a table was in create flow or in the enable flow.
Previously the ENABLING state was in master fail over scenario.

Pls provide your inputs.

                
> Master restart on create table with splitkeys does not recreate table with all the splitkey regions
> ---------------------------------------------------------------------------------------------------
>
>                 Key: HBASE-5583
>                 URL: https://issues.apache.org/jira/browse/HBASE-5583
>             Project: HBase
>          Issue Type: Bug
>            Reporter: ramkrishna.s.vasudevan
>            Assignee: ramkrishna.s.vasudevan
>             Fix For: 0.96.0
>
>
> -> Create table using splitkeys
> -> MAster goes down before all regions are added to meta
> -> On master restart the table is again enabled but with less number of regions than specified in splitkeys
> Anyway client will get an exception if i had called sync create table.  But table exists or not check will say table exists. 
> Is this scenario to be handled by client only or can we have some mechanism on the master side for this? Pls suggest.

--
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