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From Robert Wille <>
Subject Re: Gotchas when creating a lot of tombstones
Date Sat, 11 Jan 2014 03:31:57 GMT
I essentially am using a time-based data model. But, if I don¹t delete
obsolete data, my database will quickly become many times larger than
necessary. After a year, it would probably be 20x the size it would be if I
cleaned out obsolete data.

Based on an analysis of my schema and access patterns, I¹m pretty confident
that things will go well. I just wish that confidence were backed up by
experience rather than conjecture.


From:  Anthony Grasso <>
Reply-To:  <>
Date:  Friday, January 10, 2014 at 7:12 PM
To:  <>
Subject:  Re: Gotchas when creating a lot of tombstones

Hi Robert, 

It sounds like you have done a fair bit investigating and testing already.
Have you considered using a time based data model to avoid doing deletions
in the database?


On Thu, Jan 9, 2014 at 1:26 PM, sankalp kohli <>
> With Level compaction, you will have some data which could not be reclaimed
> with gc grace=0 because it has not compacted yet. For this you might want to
> look at tombstone_threshold
> On Wed, Jan 8, 2014 at 10:31 AM, Tyler Hobbs <> wrote:
>> On Wed, Jan 1, 2014 at 7:53 AM, Robert Wille <> wrote:
>>> Also, for this application, it would be quite reasonable to set gc grace
>>> seconds to 0 for these tables. Zombie data wouldn¹t really be a problem. The
>>> background process that cleans up orphaned browse structures would simply
>>> re-delete any deleted data that reappeared.
>> If you can set gc grace to 0, that will basically eliminate your tombstone
>> concerns entirely, so I would suggest that.
>> -- 
>> Tyler Hobbs
>> DataStax <>

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