I can't think of anything special about the topics besides the clients being very old (Java wrappers over Scala).
I do think it was using ack=0. But my guess is that the logging was done by the Kafka producer thread. My application itself was not getting exceptions from Kafka. On Thu, Dec 17, 2015 at 2:31 PM, Jun Rao <j...@confluent.io> wrote: > Hmm, anything special with those 3 topics? Also, the broker log shows that > the producer uses ack=0, which means the producer shouldn't get errors like > leader not found. Could you clarify on the ack used by the producer? > > Thanks, > > Jun > > On Thu, Dec 17, 2015 at 12:41 PM, Rajiv Kurian <ra...@signalfx.com> wrote: > > > The topic which stopped working had clients that were only using the old > > Java producer that is a wrapper over the Scala producer. Again it seemed > to > > work perfectly in another of our realms where we have the same topics, > same > > producers/consumers etc but with less traffic. > > > > On Thu, Dec 17, 2015 at 12:23 PM, Jun Rao <j...@confluent.io> wrote: > > > > > Are you using the new java producer? > > > > > > Thanks, > > > > > > Jun > > > > > > On Thu, Dec 17, 2015 at 9:58 AM, Rajiv Kurian <ra...@signalfx.com> > > wrote: > > > > > > > Hi Jun, > > > > Answers inline: > > > > > > > > On Thu, Dec 17, 2015 at 9:41 AM, Jun Rao <j...@confluent.io> wrote: > > > > > > > > > Rajiv, > > > > > > > > > > Thanks for reporting this. > > > > > > > > > > 1. How did you verify that 3 of the topics are corrupted? Did you > use > > > > > DumpLogSegments tool? Also, is there a simple way to reproduce the > > > > > corruption? > > > > > > > > > No I did not. The only reason I had to believe that was no writers > > could > > > > write to the topic. I have actually no idea what the problem was. I > saw > > > > very frequent (much more than usual) messages of the form: > > > > INFO [kafka-request-handler-2 ] [kafka.server.KafkaApis > > > > ]: [KafkaApi-6] Close connection due to error handling produce > > > > request with correlation id 294218 from client id with ack=0 > > > > and also message of the form: > > > > INFO [kafka-network-thread-9092-0 ] [kafka.network.Processor > > > > ]: Closing socket connection to /some ip > > > > The cluster was actually a critical one so I had no recourse but to > > > revert > > > > the change (which like noted didn't fix things). I didn't have enough > > > time > > > > to debug further. The only way I could fix it with my limited Kafka > > > > knowledge was (after reverting) deleting the topic and recreating it. > > > > I had updated a low priority cluster before that worked just fine. > That > > > > gave me the confidence to upgrade this higher priority cluster which > > did > > > > NOT work out. So the only way for me to try to reproduce it is to try > > > this > > > > on our larger clusters again. But it is critical that we don't mess > up > > > this > > > > high priority cluster so I am afraid to try again. > > > > > > > > > 2. As Lance mentioned, if you are using snappy, make sure that you > > > > include > > > > > the right snappy jar (1.1.1.7). > > > > > > > > > Wonder why I don't see Lance's email in this thread. Either way we > are > > > not > > > > using compression of any kind on this topic. > > > > > > > > > 3. For the CPU issue, could you do a bit profiling to see which > > thread > > > is > > > > > busy and where it's spending time? > > > > > > > > > Since I had to revert I didn't have the time to profile. Intuitively > it > > > > would seem like the high number of client disconnects/errors and the > > > > increased network usage probably has something to do with the high > CPU > > > > (total guess). Again our other (lower traffic) cluster that was > > upgraded > > > > was totally fine so it doesn't seem like it happens all the time. > > > > > > > > > > > > > > Jun > > > > > > > > > > > > > > > On Tue, Dec 15, 2015 at 12:52 PM, Rajiv Kurian <ra...@signalfx.com > > > > > > wrote: > > > > > > > > > > > We had to revert to 0.8.3 because three of our topics seem to > have > > > > gotten > > > > > > corrupted during the upgrade. As soon as we did the upgrade > > producers > > > > to > > > > > > the three topics I mentioned stopped being able to do writes. The > > > > clients > > > > > > complained (occasionally) about leader not found exceptions. We > > > > restarted > > > > > > our clients and brokers but that didn't seem to help. Actually > even > > > > after > > > > > > reverting to 0.8.3 these three topics were broken. To fix it we > had > > > to > > > > > stop > > > > > > all clients, delete the topics, create them again and then > restart > > > the > > > > > > clients. > > > > > > > > > > > > I realize this is not a lot of info. I couldn't wait to get more > > > debug > > > > > info > > > > > > because the cluster was actually being used. Has any one run into > > > > > something > > > > > > like this? Are there any known issues with old > consumers/producers. > > > The > > > > > > topics that got busted had clients writing to them using the old > > Java > > > > > > wrapper over the Scala producer. > > > > > > > > > > > > Here are the steps I took to upgrade. > > > > > > > > > > > > For each broker: > > > > > > > > > > > > 1. Stop the broker. > > > > > > 2. Restart with the 0.9 broker running with > > > > > > inter.broker.protocol.version=0.8.2.X > > > > > > 3. Wait for under replicated partitions to go down to 0. > > > > > > 4. Go to step 1. > > > > > > Once all the brokers were running the 0.9 code with > > > > > > inter.broker.protocol.version=0.8.2.X we restarted them one by > one > > > with > > > > > > inter.broker.protocol.version=0.9.0.0 > > > > > > > > > > > > When reverting I did the following. > > > > > > > > > > > > For each broker. > > > > > > > > > > > > 1. Stop the broker. > > > > > > 2. Restart with the 0.9 broker running with > > > > > > inter.broker.protocol.version=0.8.2.X > > > > > > 3. Wait for under replicated partitions to go down to 0. > > > > > > 4. Go to step 1. > > > > > > > > > > > > Once all the brokers were running 0.9 code with > > > > > > inter.broker.protocol.version=0.8.2.X I restarted them one by > one > > > with > > > > > the > > > > > > 0.8.2.3 broker code. This however like I mentioned did not fix > the > > > > three > > > > > > broken topics. > > > > > > > > > > > > > > > > > > On Mon, Dec 14, 2015 at 3:13 PM, Rajiv Kurian < > ra...@signalfx.com> > > > > > wrote: > > > > > > > > > > > > > Now that it has been a bit longer, the spikes I was seeing are > > gone > > > > but > > > > > > > the CPU and network in/out on the three brokers that were > showing > > > the > > > > > > > spikes are still much higher than before the upgrade. Their > CPUs > > > have > > > > > > > increased from around 1-2% to 12-20%. The network in on the > same > > > > > brokers > > > > > > > has gone up from under 2 Mb/sec to 19-33 Mb/sec. The network > out > > > has > > > > > gone > > > > > > > up from under 2 Mb/sec to 29-42 Mb/sec. I don't see a > > corresponding > > > > > > > increase in kafka messages in per second or kafka bytes in per > > > second > > > > > JMX > > > > > > > metrics. > > > > > > > > > > > > > > Thanks, > > > > > > > Rajiv > > > > > > > > > > > > > > > > > > > > > > > > > > > >