ReadMe

This scripts provide details related to various caches used in Oak MongoMK module while running within Sling OSGi Container
The script is based on (JAMM) [1]. Steps are provided below
 
1. Download JAMM from Maven
    $wget http://repo1.maven.org/maven2/com/github/stephenc/jamm/0.2.5/jamm-0.2.5.jar
2. Modify the Quickstart launching by specifying agent and bootdelegation list
    $java -javaagent:<path to>/jamm.jar -Dorg.apache.sling.launcher.bootdelegation=,org.github.jamm -jar
3. Deploy the Script Console jar
    $wget http://repo1.maven.org/maven2/org/apache/sling/org.apache.sling.scripting.console/1.0.0/org.apache.sling.scripting.console-1.0.0.jar
    $wget http://repo1.maven.org/maven2/org/codehaus/groovy/groovy-all/2.1.3/groovy-all-2.1.3.jar
    $curl -u admin:admin -F action=install -F bundlestartlevel=20 -F bundlefile=@"org.apache.sling.scripting.console-1.0.0.jar"   http://localhost:4502/system/console/bundles
    $curl -u admin:admin -F action=install -F bundlestartlevel=20 -F bundlefile=@"groovy-all-2.1.3.jar" http://localhost:4502/system/console/bundles
4. Access http://localhost:4502/system/console/scriptconsole and execute the script
 
 
[1] https://github.com/jbellis/jamm
[2] http://stackoverflow.com/a/3758880/1035417

sizeOf.groovy

import org.github.jamm.*

//Globals  
mk = sling.getService(org.apache.jackrabbit.mk.api.MicroKernel.class)
nodeStore = sling.getService(org.apache.jackrabbit.oak.spi.state.NodeStore.class)
meter = new org.github.jamm.MemoryMeter();

println "Cache Info " 
println "--------------"
displayStats("Node Cache",mk.nodeCache)
displayStats("Node Children Cache", mk.nodeChildrenCache)
displayStats("Document Cache", mk.store.nodesCache)
//displayStats("Kernal Node Store Cache", nodeStore.cache)

def displayStats(String name, def cache){
  println name
  println "    Size : Actual (Allocated) ${prettyfy(meter.measureDeep(cache))} (${prettyfy(cache.asMap().@maxWeight)})"
  println "    Stats : " + cache.stats()
  println "    No of entries : " + cache.size()
}

//Based on http://stackoverflow.com/a/3758880/1035417
def String prettyfy(long bytes) {
    boolean si = true
    int unit = si ? 1000 : 1024;
    if (bytes < unit) return bytes + " B";
    int exp = (int) (Math.log(bytes) / Math.log(unit));
    String pre = "" + (si ? "kMGTPE" : "KMGTPE").charAt(exp-1) + (si ? "" : "i");
    return String.format("%.1f %sB", bytes / Math.pow(unit, exp), pre);
}