}
public Integer sum(){ // used in sanity checks only
Integer sum=0;
INode pred = null, curr = null,front=null, end=null;
Address server=null,predServer = null, currServer=null, endServer=null;
String predId=null, firstId=null, currId=null;
try {
//Get a lock on front and end node so no one else can delete the nodes in queue
//While traversing through it
server = (Address) Network.getAddress(Benchmark.getServerId(HEAD));