To run the system test we need to create processing containers that we can
spawn tasks, called Instances, in. (how is that for a dangling preposition!?!)
Start up InstanceContainers first. Then run the system test. The system test
finds the InstanceContainers and directs them through ZooKeeper, so you are
going to need an instance of ZooKeeper running that they can all access.
The easiest way to do all of this is to use the zookeeper fat jar.

Steps to run system test
------------------------
1) build and transfer the fatjar from the `zookeeper-contrib/zookeeper-contrib-fatjar/target`
   directory to all systems participating in the test

   Command to build fatjar without executing the tests:

   `mvn clean install -P fatjar -DskipTests`

2) run a zookeeper standalone instance (cluster is ok too)

e.g. java -jar zookeeper-<version>-fatjar.jar server <zoo.cfg>

Note: you must provide zoo.cfg, see sample in conf directory

3) on each host start the system test container

e.g. java -jar zookeeper-<version>-fatjar.jar ic <name> <zkHostPort> /sysTest

name : name of the test container - must be unique 
  typically it's a good idea to name after the host to aid debugging

zkHostPort : the host:port of the server from step 2)

4) initiate the system test using the fatjar:

java -jar build/contrib/fatjar/zookeeper-<version>-fatjar.jar systest org.apache.zookeeper.test.system.SimpleSysTest

by default it will access the zk server started in 2) on localhost:2181 

or you can specify a remote host:port using
  -DsysTest.zkHostPort=<host>:<port>,<host>:<port>,...

java -DsysTest.zkHostPort=hostA:2181  -jar build/contrib/fatjar/zookeeper-<version>-fatjar.jar systest org.apache.zookeeper.test.system.SimpleSysTest

where hostA is running the zk server started in step 2) above

InstanceContainers can also be used to run a the saturation benchmark. The
first two steps are the same as the system test. Step 3 is almost the same:

3) start the InstanceContainer on each host:

e.g. java -jar zookeeper-<version>-fatjar.jar ic <name> <zkHostPort> <prefix>

note prefix can be /sysTest or any other path. If you do use /sysTest, make
sure the system test isn't running when you run the benchmark.

4) run GenerateLoad using the following

java -jar build/contrib/fatjar/zookeeper-<version>-fatjar.jar generateLoad <zkHostPort> <prefix> #servers #clients

Once GenerateLoad is started, it will read commands from stdin. Usually
the only command you need to know is "percentage" which sets the percentage
of writes to use in the requests. Once a percentage is set, the benchmark
will start. "percentage 0" will cause only reads to be issued and
"percentage 100" will cause only writes to be issued.