I haven't heard of anybody setting the niceness of the Accumulo processes before. Are you experiencing a lot of CPU contention on your nodes, such that you need to prioritize processes?
However, if you do this, I think you actually want HDFS to -2, Accumulo to -1, and Mapreduce tasks 0 (you'll have to edit the system security limits to allow niceness below 0 for non-root users). Otherwise, you're lowering the priority, not increasing it (and lowering it below other, normal user processes, since the default niceness is 0). -- Christopher L Tubbs II http://gravatar.com/ctubbsii On Mon, Aug 17, 2015 at 5:21 PM, Jeff Kubina <[email protected]> wrote: > On each of the processing nodes in our cluster we have running 1) HDFS > (datanode), 2) Accumulo (tablet server), and 3) Hadoop. Since Accumulo > depends on the HDFS, and Hadoop depends on the HDFS and sometimes on > Accumulo, we are considering setting the niceness of HDFS to 0 (the current > value), Accumulo to 1, and Hadoop to 2 on each of the nodes. The objective > is to improve the real time performance of Accumulo. > > Does anyone have experience configuring their cluster in a similar manner > that they can share? Are there any serious cons to doing this? >
