Hi,
Would you consider using memcached or redis for cross bolt counters, or do you have any requirement to perform the increments inside the Bolt? see also: http://storm.incubator.apache.org/documentation/Common-patterns.html? Regards, Itai ________________________________ From: 이승진 <[email protected]> Sent: Monday, October 13, 2014 4:39 AM To: [email protected] Subject: regarding shared componenets of a single bolt Dear all, One simple question about parallelism of storm and shared variables. If I set parallelism count to 4 for example, and there are some member variables in that bolt. Is it shared across 4 bolts or not? Seems like each is seperate object and they don't share nothing, which is the opposite way from what I expected. For example, if I run this bolt in local mode, 4 counters is being incremented seperately, public class PercolatorBolt extends BaseBasicBolt { private int i = 0; @Override public void prepare(Map stormConf, TopologyContext context) { } public void execute(Tuple tuple, BasicOutputCollector collector) { synchronized(this){ System.out.println(i++); } } } I want to here from you about this topic, thanks. Sincerely, [http://ack.mail.navercorp.com/readReceipt/notify/?img=rfnmFqKrFxudKA2YaqumFxE%2FMxISKoiCK4KrMxJoMrtqM6E%2FKzUqa6F4pEIo%2BrkSKAu5W49vpSl51zlqDBFdp6d5MreRhoR9brkZtHFdWXiR74JmM6FcpLlTb4b%3D.gif]
