cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From cem <>
Subject virtual nodes + map reduce = too many mappers
Date Fri, 15 Feb 2013 16:52:33 GMT
Hi All,

I have just started to use virtual nodes. I set the number of nodes to 256
as recommended.

The problem that I have is when I run a mapreduce job it creates node * 256
mappers. It creates node * 256 splits. this effects the performance since
the range queries have a lot of overhead.

Any suggestion to improve the performance? It seems like I need to lower
the  number of virtual nodes.

Best Regards,

View raw message