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https://issues.apache.org/jira/browse/HBASE-16210?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Sai Teja Ranuva updated HBASE-16210:
------------------------------------
    Attachment: HBASE-16210.master.8.patch

1. Changed the Timestamp Implementation to Enum completely.
2. Changed the Timestamp semantics. Instead of HLC, System monotonic and  
custom, we now have Hybrid and Physical. System monotonic clock and Custom 
clocks can map their timestamps to Physical. HLC clock can map its timestamp to 
Hybrid.
3. The HTableDescriptor will contain clock type(not implemented yet) instead of 
timestamp type. As clocks convey the semantics of monotonic increasing and non 
decreasing etc. TimestampType doesn't have those semantics enforced, it just 
knows what to do with given 64 bits. Therefore, I removed the timestamp type 
field in the HTableDescriptor. 

Open for suggestions. 



> Add Timestamp class to the hbase-common and Timestamp type to HTable.
> ---------------------------------------------------------------------
>
>                 Key: HBASE-16210
>                 URL: https://issues.apache.org/jira/browse/HBASE-16210
>             Project: HBase
>          Issue Type: Sub-task
>            Reporter: Sai Teja Ranuva
>            Assignee: Sai Teja Ranuva
>            Priority: Minor
>              Labels: patch, testing
>         Attachments: HBASE-16210.master.1.patch, HBASE-16210.master.2.patch, 
> HBASE-16210.master.3.patch, HBASE-16210.master.4.patch, 
> HBASE-16210.master.5.patch, HBASE-16210.master.6.patch, 
> HBASE-16210.master.7.patch, HBASE-16210.master.8.patch
>
>
> This is a sub-issue of 
> [HBase-14070|https://issues.apache.org/jira/browse/HBASE-14070]. This JIRA is 
> a small step towards completely adding Hybrid Logical Clocks(HLC) to HBase. 
> The main idea of HLC is described in 
> [HBase-14070|https://issues.apache.org/jira/browse/HBASE-14070] along with 
> the motivation of adding it to HBase. 
> What is this patch/issue about ?
> This issue attempts to add a timestamp class to hbase-common and timestamp 
> type to HTable. 
> This is a part of the attempt to get HLC into HBase. This patch does not 
> interfere with the current working of HBase.
> Why Timestamp Class ?
> Timestamp class can be as an abstraction to represent time in Hbase in 64 
> bits. 
> It is just used for manipulating with the 64 bits of the timestamp and is not 
> concerned about the actual time.
> There are three types of timestamps. System time, Custom and HLC. Each one of 
> it has methods to manipulate the 64 bits of timestamp. 
> HTable changes: Added a timestamp type property to HTable. This will help 
> HBase exist in conjunction with old type of timestamp and also the HLC which 
> will be introduced. The default is set to custom timestamp(current way of 
> usage of timestamp). default unset timestamp is also custom timestamp as it 
> should be so. The default timestamp will be changed to HLC when HLC feature 
> is introduced completely in HBase.
> Check HBASE-16210.master.6.patch.
> Suggestions are welcome.



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