I'm not sure, I would have to run a test to see if this is possible. Maybe someone else knows off hand. If it's possible to re-emit while the tuple is still enqueued, I can see how you might run into a situation where you can never work the queue off. On Jan 28, 2015 4:56 PM, "Tao, Jing" <[email protected]> wrote:
> Can multiple copies of the same tuple be in the queue at the same time? > Say 1999 tuples timeout, the queue is still reduced to size 1999, correct? > What I’m seeing is that the queue size seems to never shrink once timeouts > start happening. > > > > I’ve seen timeouts previously due to large volume of data, but they did > clear up after a few minutes. > > This time, it did not clear after even 2 hours. The Spout’s Acked # > stayed the same for 2 hours. > > > > *From:* Nathan Leung [mailto:[email protected]] > *Sent:* Wednesday, January 28, 2015 4:20 PM > *To:* user > *Subject:* Re: Timed-out tuples replayed over and over > > > > Your max spout pending is 2000. In a worst case scenario, where you have > 1 spout task, 1 bolt task, and every request is timing out, if your spout > output queue is full it will take 4000 seconds to drain. This is not > accounting for any tuples that need to be replayed, which will cause the > full queue drain to take even longer. > > > > On Wed, Jan 28, 2015 at 4:13 PM, Tao, Jing <[email protected]> wrote: > > Hi, > > > > I have a topology where one of the bolts is taking 2 seconds to complete > due to a webservice call which is timing out (I set request timeout to 2 > sec). > > > > I have the following configs for the topology: > > config.put(Config.TOPOLOGY_MESSAGE_TIMEOUT_SECS, 60) > > config.setMaxSpoutPending(2000) > > config.setNumAckers(4) > > config.setNumWorkers(3) > > > > What I am seeing is, many message will timeout, and gets replayed every > few minutes. I’m assuming they are repeatedly timing out? But if each > tuple takes 2 seconds, and TOPOLOGY_MESSAGE_TIMEOUT_SECS is 60, why are > they timing out so much? I had a total of 2250 tuples, and the queue still > has not cleared up after almost 2 hours. > > > > When the webservice call does not timeout, 2250 tuples only takes a few > minutes to complete. > > > > Any ideas? > > > > Thanks, > > Jing > > >
