incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Omid Aladini <>
Subject Re: Nodetool repair and Leveled Compaction
Date Wed, 26 Sep 2012 10:37:54 GMT
I think this JIRA answers your question:

which in order not to duplicate work (creation of Merkle trees) repair
is done on all replicas for a range.


On Tue, Sep 25, 2012 at 8:27 AM, Sergey Tryuber <> wrote:
> Hi Radim
> Unfortunately number of compaction tasks is not overestimated. The number is
> decremented one-by-one and this process takes several hours for our 40GB
> node(( Also, when a lot of compaction tasks appears, we see that total disk
> space used (via JMX) is doubled and Cassandra really tries to compact
> something. When compactions are done, "total disk space used" is back to
> normal.
> On 24 September 2012 19:04, Radim Kolar <> wrote:
>>> Repair process by itself is going well in a background, but the issue I'm
>>> concerned is a lot of unnecessary compaction tasks
>> number in compaction tasks counter is over estimated. For example i have
>> 1100 tasks left and if I will stop inserting data, all tasks will finish
>> within 30 minutes.
>> I suppose that this counter is incremented for every sstable which needs
>> compaction, but its not decremented properly because you can compact about
>> 20 sstables at once, and this reduces counter only by 1.

View raw message