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From Billy Liu <>
Subject Re: How to clean up after Kylin 2.0
Date Wed, 17 May 2017 02:50:28 GMT
Thanks Itay for raising this question.

When you rebuild the cube, the old segment will be invalid for query, but
available for cleanup. The StorageCleanupJob should clean those files, but
if not, that may be an issue. Could you log a JIRA for this issue and
describe how to reproduce it? That will help community to fix it a.s.a.p.

Kylin will save duplicate cube data on both HDFS and HBase. The HBase one
is used for query, the HDFS one is used for later segment merge. If no
merged needed, it's safe to delete it manually.

2017-05-17 0:55 GMT+08:00 Itay Shwartz <>:

> Hi,
> I work on a project where we build a cube multiple times a day using
> Kylin. We were using Kylin 1.6 and upgraded this week to Kylin 2.0.
> Since the upgrade I noticed that the HDFS usage had increased every time
> we rebuild the cube and the space is not cleared up. This is although we
> run both the StorageCleanupJob and metastore clean command as described
> here and here.
> When looking into HDFS to see where the increase is I see that the
> accumulated data is at: /kylin/kylin_metadata/
> It looks like every job is getting a new folder inside that folder and its
> size is at least the same as the size of the cube. Seems like some of these
> folders were not cleared even for very old jobs but since the upgrade to
> V2.0 all the folders for all jobs were not cleared. I deleted some of the
> older folders and it didn't affect the cube. I also created a test cube and
> then deleted the folder that was created for it and could still query the
> cube. Is it safe to delete these folders manually? Is it correct to assume
> that after the job is done all the data that needs to be maintained will be
> in HBase (Where I can find the cube and the metadata information)?
> Many thanks,
> Itay
> -----
> Itay Shwartz
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