don't set -XX:MetaspaceSize= setting since it can prevent cleanup of …

…allocated native memory

docs/jre-open_jdk_jre.md

@@ -39,7 +39,7 @@ The following optional properties may be specified in the `memory_sizes` mapping
 | Name | Description
 | ---- | -----------
 | `heap` | The maximum heap size to use. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line options `-Xmx` and `-Xms`.
-| `metaspace` | The maximum Metaspace size to use. It is applicable to versions of OpenJDK from 1.8 onwards. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line options `-XX:MaxMetaspaceSize=` and `-XX:MetaspaceSize=`.
+| `metaspace` | The maximum Metaspace size to use. It is applicable to versions of OpenJDK from 1.8 onwards. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line options `-XX:MaxMetaspaceSize=`.
 | `native` | The amount of memory to reserve for native memory allocation. It should normally be omitted or specified as a range with no upper bound such as `100m..`. It does not correspond to a switch on the Java command line.
 | `permgen` | The maximum PermGen size to use. It is applicable to versions of OpenJDK earlier than 1.8. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line options `-XX:MaxPermSize=` and `-XX:PermSize=`.
 | `stack` | The stack size to use. It may be a single value such as `2m` or a range of acceptable values such as `2m..4m`. It is used to calculate the value of the Java command line option `-Xss`.

docs/jre-oracle_jre.md

@@ -48,7 +48,7 @@ The following optional properties may be specified in the `memory_sizes` mapping
 | Name | Description
 | ---- | -----------
 | `heap` | The maximum heap size to use. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line options `-Xmx` and `-Xms`.
-| `metaspace` | The maximum Metaspace size to use. It is applicable to versions of Oracle from 1.8 onwards. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line options `-XX:MaxMetaspaceSize=` and `-XX:MetaspaceSize=`.
+| `metaspace` | The maximum Metaspace size to use. It is applicable to versions of Oracle from 1.8 onwards. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line option `-XX:MaxMetaspaceSize=`.
 | `native` | The amount of memory to reserve for native memory allocation. It should normally be omitted or specified as a range with no upper bound such as `100m..`. It does not correspond to a switch on the Java command line.
 | `permgen` | The maximum PermGen size to use. It is applicable to versions of Oracle earlier than 1.8. It may be a single value such as `64m` or a range of acceptable values such as `128m..256m`. It is used to calculate the value of the Java command line options `-XX:MaxPermSize=` and `-XX:PermSize=`.
 | `stack` | The stack size to use. It may be a single value such as `2m` or a range of acceptable values such as `2m..4m`. It is used to calculate the value of the Java command line option `-Xss`.

lib/java_buildpack/jre/memory/openjdk_memory_heuristic_factory.rb

@@ -47,7 +47,7 @@ def create_memory_heuristic(sizes, heuristics, version)
 
         JAVA_OPTS = {
           'heap'      => ->(v) { %W(-Xmx#{v} -Xms#{v}) },
-          'metaspace' => ->(v) { %W(-XX:MaxMetaspaceSize=#{v} -XX:MetaspaceSize=#{v}) },
+          'metaspace' => ->(v) { %W(-XX:MaxMetaspaceSize=#{v}) },
           'permgen'   => ->(v) { %W(-XX:MaxPermSize=#{v} -XX:PermSize=#{v}) },
           'stack'     => ->(v) { ["-Xss#{v}"] }
         }.freeze

spec/java_buildpack/jre/memory/openjdk_memory_heuristic_factory_spec.rb

@@ -42,7 +42,7 @@
   let(:expected_java_memory_options) do
     {
       'heap'      => ->(v) { %W(-Xmx#{v} -Xms#{v}) },
-      'metaspace' => ->(v) { %W(-XX:MaxMetaspaceSize=#{v} -XX:MetaspaceSize=#{v}) },
+      'metaspace' => ->(v) { %W(-XX:MaxMetaspaceSize=#{v}) },
       'permgen'   => ->(v) { %W(-XX:MaxPermSize=#{v} -XX:PermSize=#{v}) },
       'stack'     => ->(v) { %W(-Xss#{v}) }
     }