Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
HBase >> mail # user >> Major vs Minor compactions


Copy link to this message
-
Re: Major vs Minor compactions
On Wed, May 29, 2013 at 1:27 PM, Varun Sharma <[EMAIL PROTECTED]> wrote:

> Hi,
>
> I am working on some compaction coprocessors for a column family with
> versions set to 1. I am using the preCompact hook to wrap a scanner around
> the compaction scanner.
>
> I wanted to know what to expect from the minor compaction output. Can I
> assume the following:
> 1) Versions for each cell will be 1
> 2) Delete markers will be retained
> 3) Corresponding versions older than the delete markers shall be removed
>
> Am I missing anything here ?
>

How you going to ensure your cp fires ONLY on a minor compaction?

In your version of hbase, minors can be promoted to be majors if all files
make it into the selection; how you going to deal?

Yeah, if minors, deletes (currently) are retained (unless promoted to
major).

At a guess, the versions should be weeded by the time your cp gets a whack
at the content (don't take my word for it though).

St.Ack