[ 
https://issues.apache.org/jira/browse/HBASE-11315?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Jeffrey Zhong updated HBASE-11315:
----------------------------------

    Release Note: 
After this patch, MVCC value of KVs will be kept for a configurable period 
"hbase.hstore.compaction.keep.mvcc.period"(default value is 5 days). The 
minimum setting of "hbase.hstore.compaction.keep.mvcc.period" is also set to 5 
days and any user setting less than the min setting will be ignored.


  was:
After this patch, MVCC value of KVs will be kept for a configurable period 
"hbase.hstore.compaction.keep.mvcc.period"(default value is 6 days). The 
minimum setting of "hbase.hstore.compaction.keep.mvcc.period" is also set to 6 
days and any user setting less than the min setting will be ignored.



> Keeping MVCC for configurable longer time 
> ------------------------------------------
>
>                 Key: HBASE-11315
>                 URL: https://issues.apache.org/jira/browse/HBASE-11315
>             Project: HBase
>          Issue Type: Improvement
>    Affects Versions: 0.99.0
>            Reporter: Jeffrey Zhong
>            Assignee: Jeffrey Zhong
>         Attachments: hbase-11315-v1.patch, hbase-11315.patch
>
>
> After hbase-8763, we need keep mvcc number longer in hfile so that it can be 
> used to order changes during writes. For example, the known 
> put,delete,put,... scenario, cross region server scan, out of order puts(in 
> recovery case).
> Current thinking is that we make the retention period configurable(below 
> we're using 1 day to explain). During major compaction, we check hfile's 
> creation time if a hfile creation time is older than 1 day then all mvcc of 
> KVs in that hfile will be removed. If a hfile is created within 1 day, then 
> all mvccs of KVs in that hfile will be kept. 
> In case there are time clock skew, we can firstly sort hfiles based on its 
> seqId in ascending order and find the first hfile's creation time stamp less 
> than 1 day. Then mvcc of all hfiles before the found file will be removed 
> during compaction. 



--
This message was sent by Atlassian JIRA
(v6.2#6252)

Reply via email to