Question

I used a while loop to fetch message from Amazon SQS. Partial code is as follows:

ReceiveMessageRequest receiveMessageRequest = new ReceiveMessageRequest(myQueueUrl);
while (true) {
    List<Message> messages = sqs.receiveMessage(receiveMessageRequest).getMessages();

     if (messages.size() > 0) {

             MemcachedClient c = new MemcachedClient(new BinaryConnectionFactory(), AddrUtil.getAddresses(memAddress));

             for (Message message : messages) {

                 // get message from aws sqs
                 String messageid = message.getBody();
                 String messageRecieptHandle = message.getReceiptHandle();
                 sqs.deleteMessage(new DeleteMessageRequest(myQueueUrl, messageRecieptHandle));

                 // get details info from memcache 
                 String result = null;
                 String key = null;
                 key = "message-"+messageid;
                 result = c.get(key);

             }
             c.shutdown();
          }
       }

Will it cause memory leak in such case?
I checked using “ps aux”. What I found is that the RSS (resident set size, the non-swapped physical memory that a task used) is growing slowly.

Answer 1

Sorry, but I don’t see here code to remove message from the message queue. Did you clean the message list? In case that DeleteRequest removes message from the queue then you try to modify message list which you itereate.

Also you can get better memory usage statistic with visualvm tool which is part of JDK now.