cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Adi <>
Subject Re: Is it safe to stop a read repair and any suggestion on speeding up repairs
Date Fri, 22 Jul 2011 14:17:49 GMT
> Short answer, yes it's safe to kill cassandra during a repair. It's one of
> the nice things about never mutating data.
> Longer answer: If nodetool compactionstats says there are no Validation
> compactions running (and the compaction queue is empty)  and netstats says
> there is nothing streaming there is a a good chance the repair is finished
> or dead. If a neighbour dies during a repair the node it was started on will
> wait for 48 hours(?) until it times out. Check the logs on the machines for
> errors, particularly from the AntiEntropyService. And see what
> compactionstats is saying on all the nodes involved in the repair.
Thanks Aaron. One of the neighboring nodes did go down due to running out of
memory so I will make sure the repair is dead and start it again per column

Even Longer: um, 3 TB of data is *way* to much data per node, generally
> happy people have up to about 200 to 300GB per node. The reason for this
> recommendation is so that things like repair, compaction, node moves, etc
> are managable  and because the loss of a single node has less of an impact.
> I would not recommend running a live system with that much data per node.
 Thanks for the advice and this can be a separate discussion but that will
make a Cassandra cluster way too costly , we would have to buy 16 systems
for the same amount of data as opposed to 4 that we have now and my IT
director will strangle me.


View raw message