incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Michał Michalski <mich...@opera.com>
Subject Re: Deletion use more space.
Date Tue, 16 Jul 2013 09:51:49 GMT
Deletion is not really "removing" data, but it's adding tombstones 
(markers) of deletion. They'll be later merged with existing data during 
compaction and - in the end (see: gc_grace_seconds) - removed, but by 
this time they'll take some space.

http://wiki.apache.org/cassandra/DistributedDeletes

M.

W dniu 16.07.2013 11:46, 杨辉强 pisze:
> Hi, all:
>    I use cassandra 1.2.4 and I have 4 nodes ring and use byte order partitioner.
>    I had inserted about 200G data in the ring previous days.
>
>    Today I write a program to scan the ring and then at the same time delete the items
that are scanned.
>    To my surprise, the cassandra cost more disk usage.
>
>     Anybody can tell me why? Thanks.
>


Mime
View raw message