It seems that JavaSE8's -XX;MetaspaceSize does not affect the initial metaspace size.
    
This is different from the behavior of -Xms and -XX:InitialCodeCodeSize. These options will set the initial commit charge for the Java Heap and CodeCache. -XX:MetaspaceSize does not affect initial metaspace commit charge."

    I have executed the JmxLoop test attached upon jdk8u25 linux+x86 JVM with several different values of JVM option InitialBootClassLoaderMetaspaceSize. Test results are shwon below.

    What is the releationship between InitialBootClassLoaderMetaspaceSize JVM option and -XX:MaxMetaspaceSize JVM option ?
    JVM options used for the tests:

                    -Xms8M -Xmx8M -XX:InitialCodeCacheSize=4M -XX:ReservedCodeCacheSize=4M \
                    -XX:+UseLargePagesInMetaspace -XX:+UseLargePages \
                    -XX:InitialBootClassLoaderMetaspaceSize=xM -XX:MaxMetaspaceSize=8M \
                    -XX:+UnlockDiagnosticVMOptions \
                    -XX:NativeMemoryTracking=summary \
                    -XX:+PrintNMTStatistics \
                    JmxLoop


     (1) -XX:InitialBootClassLoaderMetaspaceSize=1M
  Metaspace
  currentUsage
  init = 0(0K) used = 1662656(1623K) committed = 4194304(4096K) max = 8388608(8192K)
  peakUsage
  init = 0(0K) used = 1662656(1623K) committed = 4194304(4096K) max = 8388608(8192K)

   (2) -XX:InitialBootClassLoaderMetaspaceSize=2M
  Metaspace
  currentUsage
  init = 0(0K) used = 1656792(1617K) committed = 4194304(4096K) max = 8388608(8192K)
  peakUsage
  init = 0(0K) used = 1656792(1617K) committed = 4194304(4096K) max = 8388608(8192K)

   (3) -XX:InitialBootClassLoaderMetaspaceSize=3M
 Metaspace
 currentUsage
 init = 0(0K) used = 1656824(1617K) committed = 4194304(4096K) max = 8388608(8192K)
 peakUsage
 init = 0(0K) used = 1656824(1617K) committed = 4194304(4096K) max = 8388608(8192K)


   (4) -XX:InitialBootClassLoaderMetaspaceSize=4M
  Metaspace
  currentUsage
  init = 0(0K) used = 1656824(1617K) committed = 8388608(8192K) max = 8388608(8192K)
  peakUsage
  init = 0(0K) used = 1656824(1617K) committed = 8388608(8192K) max = 8388608(8192K)

   (5) -XX:InitialBootClassLoaderMetaspaceSize=5M
  Metaspace
  currentUsage
  init = 0(0K) used = 1656824(1617K) committed = 8388608(8192K) max = 8388608(8192K)
  peakUsage
  init = 0(0K) used = 1656824(1617K) committed = 8388608(8192K) max = 8388608(8192K)

Why does the committed metaspace size become 4M * 2 = 8M in case that -XX:InitialBootClassLoaderMetaspaceSize is specified as 4M or larger?
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