[ 
https://issues.apache.org/jira/browse/PHOENIX-2417?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15068442#comment-15068442
 ] 

James Taylor commented on PHOENIX-2417:
---------------------------------------

With PHOENIX-2143, the compression would only be to reduce memory usage (which 
is the main reason we want to do it), not on disk memory. The compression would 
be done for the guideposts stored in GuidePostsInfo which is transmitted over 
the wire as part of the PTable and cached on the client and server side.

> Compress memory used by row key byte[] of guideposts
> ----------------------------------------------------
>
>                 Key: PHOENIX-2417
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-2417
>             Project: Phoenix
>          Issue Type: Sub-task
>            Reporter: James Taylor
>            Assignee: Samarth Jain
>             Fix For: 4.7.0
>
>
> We've found that smaller guideposts are better in terms of minimizing any 
> increase in latency for point scans. However, this increases the amount of 
> memory significantly when caching the guideposts on the client. Guidepost are 
> equidistant row keys in the form of raw byte[] which are likely to have a 
> large percentage of their leading bytes in common (as they're stored in 
> sorted order. We should use a simple compression technique to mitigate this. 
> I noticed that Apache Parquet has a run length encoding - perhaps we can use 
> that.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to