A quick and dirty Groovy script to monitor Mongo connections for a short time

monogo-mbean.groovy

import javax.management.remote.*
import javax.management.*
import groovy.jmx.builder.*

// see https://mongodb.github.io/mongo-java-driver/3.0/driver/reference/management/monitoring/
attrs = ['CheckedOutCount','MinSize','MaxSize','WaitQueueSize','Size']

def print_mbeans(def mbeans) {

   def webBean = mbeans.queryNames(new ObjectName('org.mongodb.driver:*'), null).find {
     name->

    def values = [ new Date() as String,  name.getKeyProperty('clusterId')]

    attrs.each { attr->
       values<<mbeans.getAttribute(name,attr)
    }

   println values.join(",")

}
}


// Setup JMX connection.
def connection = new JmxBuilder().client(port: 8991, host: 'localhost')
connection.connect()

// Get the MBeanServer.
def mbeans = connection.MBeanServerConnection

print "Date,ClusterId,"
println attrs.join(",")
// change 10 to however many seconds you want this to run
(1..10).each {
   print_mbeans(mbeans)
   Thread.sleep(1000)
}

print "Done!"