On all but the largest clusters, the computing needs of the master/gc/monitor/tracer can all run on one node and can be co-located with a zookeeper server.
Strictly speaking, you don't need a tracer. Unless you are running a very large cluster, one tracer will be enough. The tracer can be used to identify components that are performing slowly, so it needs to run all the time. -Eric On Wed, May 1, 2013 at 3:57 PM, Aaron G <[email protected]> wrote: > Generic/best practices question about the 6 services: master, gc, > tserver, logger, monitor, tracer > > For this example/discussion let's say I have a cluster, with 10 nodes > (n01-n10)...3 of the nodes running zookeeper > > n01: NameNode, zooKeeper > n02: SecondaryNameNode, zooKeeper > n03: JobTracker, zooKeeper > n04: empty (for now) > > Let's label these storage/compute nodes: > n05-n10: dataNode, taskTracker > > So, how i thought this could be setup for Accumulo services: > > n04: master & gc > n05-n10: each runs a tserver & logger > > I think my main questions revolve around the monitor & tracer services and > where they run: > > 1. Does those need to run on every "compute node"? > 2. Do you only need one running instance of monitor? Perhaps on the n04? > Or does it need to run on every tserver as well? > 3. Do you only need the tracer service running on compute nodes? Or > everywhere (master & gc included)? Do you only need the tracer for the > purpose of development of Iterators, Scanners, Writers? They primarily > there to help with that activity? Or are they useful to have running "all > the time?" > > Thanks in advance, > Aaron >
