z2-Environment

Hadoop makes its log output available via JMX by providing the number of log entries by log level in an MBean:

Output of http://localhost:50070/jmx?qry=Hadoop:service=NameNode,name=JvmMetrics

{
  "beans" : [ {
    "name" : "Hadoop:service=NameNode,name=JvmMetrics",
    "modelerType" : "JvmMetrics",
    "tag.Context" : "jvm",
    "tag.ProcessName" : "NameNode",
    "tag.SessionId" : null,
    "tag.Hostname" : "ifish.fritz.box",
    "MemNonHeapUsedM" : 46.26464,
    "MemNonHeapCommittedM" : 48.875,
    "MemNonHeapMaxM" : -1.0,
    "MemHeapUsedM" : 243.12225,
    "MemHeapCommittedM" : 483.0,
    "MemHeapMaxM" : 889.0,
    "MemMaxM" : 889.0,
    "GcCount" : 4,
    "GcTimeMillis" : 55,
    "GcNumWarnThresholdExceeded" : 0,
    "GcNumInfoThresholdExceeded" : 0,
    "GcTotalExtraSleepTime" : 144,
    "ThreadsNew" : 0,
    "ThreadsRunnable" : 8,
    "ThreadsBlocked" : 0,
    "ThreadsWaiting" : 6,
    "ThreadsTimedWaiting" : 88,
    "ThreadsTerminated" : 0,
    "LogFatal" : 0,
    "LogError" : 1,
    "LogWarn" : 4,
    "LogInfo" : 151
  }

Find a sample implementation in the attachments