Performance problem - XML and Hashtable

Question

Hello!
I have a strange (or not strange, we don't know) performance problem. The situation is simple: our application runs on Oracle IAS, and gets XML messages from an MQ, and we have to process them.
Sample message:
<RequestDeal RequestId="RequestDeal-20090209200010-998493885" CurrentFragment="0" EndFragment="51" Expires="2009-03-7T08:00:10">
     <Deal>
          <Id>385011</Id>
          <ModifyDate>2009-02-09</ModifyDate>
          <PastDuesOnly>false</PastDuesOnly>
     </Deal>
     <Deal>
          <Id>385015</Id>
          <ModifyDate>2009-02-09</ModifyDate>
          <PastDuesOnly>false</PastDuesOnly>
     </Deal>
</RequestDeal>(there's an average of 50000-80000 deals in the whole message)
After the application receives the whole message, we'd like to parse it, and put the values into a hashtable for further processing:
    Hashtable ht = new Hashtable();
    Node eDeals = getElementNode(docReq, "/RequestDeal");
    Node eDeal = (Element)(eDeals.getFirstChild());
    long start = System.currentTimeMillis();
    while (eDeal != null) {
      String id = getElementText((Element)eDeal, "Id");
      Date modifyDate = getElementDateValue((Element)eDeal, "ModifyDate");
      boolean szukitett = getElementBool((Element)eDeal, "PastDuesOnly", false);
      ht.put(id, new UgyletStatusz(id, modifyDate, szukitett));
      eDeal = eDeal.getNextSibling();
    logger.info("Request adatok betöltve.");
    long end = System.currentTimeMillis();
    logger.info("Hosszu muvelet ideje: " + (end - start) + "ms");The problem is the while statement. On my PC it runs for 15-25 seconds, depends on the number of the deals; but on our customer's server, it runs for 2-5 hours with very high CPU load. The application uses oracle xml parser.
On my PC there are Websphere MQ 5.3 and Oracle 10ias with 1.5 JVM.
On our customers's server there are Websphere MQ 5.3 and Oracle 9ias with 1.4 HotSpot JVM.
Do you have any idea, what can be the cause of the problem?

Answer 1

gyulaur wrote:
Hello!
The problem is the while statement. On my PC it runs for 15-25 seconds, depends on the number of the deals; but on our customer's server, it runs for 2-5 hours with very high CPU load. The application uses oracle xml parser.
On my PC there are Websphere MQ 5.3 and Oracle 10ias with 1.5 JVM.
On our customers's server there are Websphere MQ 5.3 and Oracle 9ias with 1.4 HotSpot JVM.
Do you have any idea, what can be the cause of the problem?All sorts of things are possible.
- MQ is configured differently. For instance transactional versus non-transactional.
- The customer uses a network (multiple computers) and you use a box (singlur) and something is using a lot of bandwidth on the network. Could be your process, one of the dependent processes or something else that has nothing to do with your system
- The processing computer is loaded with something else or something is artificially limiting the processing time of your application (there is a app that allows one to limit another app to one CPU.)
- At least one version of 1.4 had a xml bug that consumed massive amounts of memory when processing large xml. Sound familar? If the physical memory is not up to it then it will be thrashing the hard drive as it swaps virtual in and out.
- Of course virtual memory causing swaps would impact it regardless of the cause.
- The database is loaded.
You can of course at least get the same version of java that they are using. Actually that would seem like a rather good idea to me regardless.