Factor out functions into bin/logstash.lib.sh to keep bin/logstash a bit

cleaner.

bin/logstash

@@ -15,56 +15,18 @@
 # in your environment and this script will download and use
 # a release of JRuby for you.
 
+# Defaults you can override with environment variables
+LS_HEAP_SIZE="${LS_HEAP_SIZE:=500m}"
+
 basedir=$(cd `dirname $0`/..; pwd)
-export RUBYLIB="$basedir/lib"
-
-setup_ruby() {
-  # Verify ruby works
-  if ! ruby -e 'puts "HURRAY"' 2> /dev/null | grep -q "HURRAY" ; then
-    echo "No ruby program found. Cannot start."
-    exit 1
-  fi
-
-  eval $(ruby -rrbconfig -e 'puts "RUBYVER=#{RbConfig::CONFIG["ruby_version"]}"; puts "RUBY=#{RUBY_ENGINE}"')
-  RUBYCMD="ruby"
-}
-
-setup_vendored_jruby() {
-  RUBYVER=1.9
-  RUBY=jruby
-
-  # Attempt faster startup; this should be for interactive or "a human is
-  # watching" execution.
-  # TODO(sissel): Add 'server' operation with good flags for that situation.
-  JAVA_OPTS="$JAVA_OPTS -client -XX:+TieredCompilation -XX:TieredStopAtLevel=1 -Djruby.compile.mode=OFF"
-  JAVA_OPTS="$JAVA_OPTS -Xmx500m"
-
-  RUBYCMD="java $JAVA_OPTS -jar $basedir/vendor/jar/jruby-complete-*.jar"
-}
-
-setup() {
-  if [ -d "$basedir/.git" -o ! -z "$USE_RUBY" ] ; then
-    setup_ruby
-  else
-    setup_vendored_jruby
-  fi
-  export GEM_HOME="$basedir/vendor/bundle/${RUBY}/${RUBYVER}"
-  export GEM_PATH=
-}
+. ${basedir}/bin/logstash.lib.sh
 
 setup
 
 case $1 in
-  deps)
-    if [ -f "$basedir/logstash.gemspec" ] ; then
-      program="$basedir/gembag.rb"
-      set -- "$basedir/logstash.gemspec"
-      exec $RUBYCMD "$basedir/gembag.rb" "$@"
-    else
-      echo "Cannot install dependencies; missing logstash.gemspec. This 'deps' command only works from a logstash git clone."
-    fi
-    ;;
-  -*)
+  deps) install_deps ;;
+  -*) 
+    # is the first argument a flag? If so, assume 'agent'
     program="$basedir/lib/logstash/runner.rb"
     exec $RUBYCMD "$program" agent "$@"
     ;;
@@ -73,4 +35,3 @@ case $1 in
     exec $RUBYCMD "$program" "$@"
     ;;
 esac
-

bin/logstash.lib.sh

@@ -0,0 +1,81 @@
+basedir=$(cd `dirname $0`/..; pwd)
+
+setup_ruby() {
+  # Verify ruby works
+  if ! ruby -e 'puts "HURRAY"' 2> /dev/null | grep -q "HURRAY" ; then
+    echo "No ruby program found. Cannot start."
+    exit 1
+  fi
+
+  eval $(ruby -rrbconfig -e 'puts "RUBYVER=#{RbConfig::CONFIG["ruby_version"]}"; puts "RUBY=#{RUBY_ENGINE}"')
+  RUBYCMD="ruby"
+}
+
+setup_java() {
+  if [ -z "$JAVA_HOME/bin/java" ] ; then
+    JAVA="$JAVA_HOME/bin/java"
+  else
+    JAVA=$(which java)
+  fi
+
+  if [ ! -x "$JAVA" ] ; then
+    echo "Could not find any executable java binary. Please install java in your PATH or set JAVA_HOME."
+    exit 1
+  fi
+
+
+  JAVA_OPTS="$JAVA_OPTS -Xmx${LS_HEAP_SIZE}"
+  JAVA_OPTS="$JAVA_OPTS -XX:+UseParNewGC"
+  JAVA_OPTS="$JAVA_OPTS -XX:+UseConcMarkSweepGC"
+  JAVA_OPTS="$JAVA_OPTS -Djava.awt.headless=true"
+
+  # Reduce per-thread stack size
+  JAVA_OPTS="$JAVA_OPTS -Xss256k"
+
+  JAVA_OPTS="$JAVA_OPTS -XX:CMSInitiatingOccupancyFraction=75"
+  JAVA_OPTS="$JAVA_OPTS -XX:+UseCMSInitiatingOccupancyOnly"
+
+  if [ ! -z "$LS_USE_GC_LOGGING" ] ; then
+    JAVA_OPTS="$JAVA_OPTS -XX:+PrintGCDetails"
+    JAVA_OPTS="$JAVA_OPTS -XX:+PrintGCTimeStamps"
+    JAVA_OPTS="$JAVA_OPTS -XX:+PrintClassHistogram"
+    JAVA_OPTS="$JAVA_OPTS -XX:+PrintTenuringDistribution"
+    JAVA_OPTS="$JAVA_OPTS -XX:+PrintGCApplicationStoppedTime"
+    JAVA_OPTS="$JAVA_OPTS -Xloggc:./logstash-gc.log"
+    echo "Writing garbage collection logs to ./logstash-gc.log"
+  fi
+} 
+
+setup_vendored_jruby() {
+  RUBYVER=1.9
+  RUBY=jruby
+
+  setup_java
+
+  RUBYCMD="$JAVA $JAVA_OPTS -jar $basedir/vendor/jar/jruby-complete-*.jar"
+}
+
+setup() {
+  if [ -z "$USE_JRUBY" -a \( -d "$basedir/.git" -o ! -z "$USE_RUBY" \) ] ; then
+    setup_ruby
+    if [ "$RUBY" = "jruby" ] ; then
+      setup_java
+      export JAVA_OPTS
+    fi
+  else
+    setup_vendored_jruby
+  fi
+  export GEM_HOME="$basedir/vendor/bundle/${RUBY}/${RUBYVER}"
+  export GEM_PATH=
+  export RUBYLIB="$basedir/lib"
+}
+
+install_deps() {
+  if [ -f "$basedir/logstash.gemspec" ] ; then
+    program="$basedir/gembag.rb"
+    set -- "$basedir/logstash.gemspec"
+    exec $RUBYCMD "$basedir/gembag.rb" "$@"
+  else
+    echo "Cannot install dependencies; missing logstash.gemspec. This 'deps' command only works from a logstash git clone."
+  fi
+}