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https://issues.apache.org/jira/browse/CARBONDATA-2889?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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kumar vishal resolved CARBONDATA-2889.
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    Resolution: Fixed

> Support Decoder based fall back mechanism in Local Dictionary
> -------------------------------------------------------------
>
>                 Key: CARBONDATA-2889
>                 URL: https://issues.apache.org/jira/browse/CARBONDATA-2889
>             Project: CarbonData
>          Issue Type: Sub-task
>            Reporter: Akash R Nilugal
>            Assignee: Akash R Nilugal
>            Priority: Major
>          Time Spent: 9h 20m
>  Remaining Estimate: 0h
>
> Currently, when the fallback is initiated for a column page in case of local 
> dictionary, we are keeping both encoded data
> and actual data in memory and then we form the new column page without 
> dictionary encoding and then at last we free the Encoded Column Page.
> Because of this offheap memory footprint increases.
>  
> We can reduce the offheap memory footprint. This can be done using decoder 
> based fallback mechanism.
> This means, no need to keep the actual data along with encoded data in 
> encoded column page. We can keep only encoded data and to form a new column 
> page, get the dictionary data from encoded column page by uncompressing and 
> using dictionary data get the actual data using local dictionary generator 
> and put it in new column page created and compress it again and give to 
> consumer for writing blocklet. 
>  
> The above process may slow down the loading, but it will reduces the memory 
> footprint. So we can give a property which will decide whether to take 
> current fallback procedure or decoder based fallback mechanism dring fallback



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