Should we still store the value bytes when logAsString is set to TRUE and only store the length when logAsString is set to FALSE.
On 6/21/15, 7:29 PM, "tao xiao" <xiaotao...@gmail.com> wrote: >The patch I submitted did the what you suggested. It store the size only >and print it out when error occurs. > >On Mon, Jun 22, 2015 at 5:26 AM Jiangjie Qin <j...@linkedin.com.invalid> >wrote: > >> Yes, we can expose a user callback in MM, just like we did for rebalance >> listener. >> I still think ErrorLoggingCallback needs some change, though. Can we >>only >> store the value bytes when logAsString is set to true? That looks more >> reasonable to me. >> >> Jiangjie (Becket) Qin >> >> On 6/21/15, 3:02 AM, "tao xiao" <xiaotao...@gmail.com> wrote: >> >> >Yes, I agree with that. It is even better if we can supply our own >> >callback. For people who want to view the content of message when >>failure >> >they still can do so >> > >> >On Sun, Jun 21, 2015 at 2:20 PM Guozhang Wang <wangg...@gmail.com> >>wrote: >> > >> >> Hi Tao / Jiangjie, >> >> >> >> I think a better fix here may be not letting >> >>MirrorMakerProducerCallback to >> >> extend from ErrorLoggingCallback, but rather change the >> >> ErrorLoggingCallback itself as it defeats the usage of logAsString, >> >>which I >> >> think is useful for a general error logging purposes. Rather we can >> >> let MirrorMakerProducerCallback >> >> to not take the value bytes itself but just the length if people >>agree >> >>that >> >> for MM we probably are not interested in its message value in >>callback. >> >> Thoughts? >> >> >> >> Guozhang >> >> >> >> On Wed, Jun 17, 2015 at 1:06 AM, tao xiao <xiaotao...@gmail.com> >>wrote: >> >> >> >> > Thank you for the reply. >> >> > >> >> > Patch submitted https://issues.apache.org/jira/browse/KAFKA-2281 >> >> > >> >> > On Mon, 15 Jun 2015 at 02:16 Jiangjie Qin >><j...@linkedin.com.invalid> >> >> > wrote: >> >> > >> >> > > Hi Tao, >> >> > > >> >> > > Yes, the issue that ErrorLoggingCallback keeps value as local >> >>variable >> >> is >> >> > > known for a while and we probably should fix it as the value is >>not >> >> used >> >> > > except logging the its size. Can you open a ticket and maybe also >> >> submit >> >> > a >> >> > > patch? >> >> > > >> >> > > For unreachable objects I don¹t think it is memory leak. As you >> >>said, >> >> GC >> >> > > should take care of this. In LinkedIn we are using G1GC with some >> >> tunings >> >> > > made by our SRE. You can try that if interested. >> >> > > >> >> > > Thanks, >> >> > > >> >> > > Jiangjie (Becket) Qin >> >> > > >> >> > > On 6/13/15, 11:39 AM, "tao xiao" <xiaotao...@gmail.com> wrote: >> >> > > >> >> > > >Hi, >> >> > > > >> >> > > >I am using mirror maker in trunk to replica data across two data >> >> > centers. >> >> > > >While the destination broker was having busy load and >>unresponsive >> >>the >> >> > > >send >> >> > > >rate of mirror maker was very low and the available producer >>buffer >> >> was >> >> > > >quickly filled up. At the end mirror maker threw OOME. Detailed >> >> > exception >> >> > > >can be found here >> >> > > > >> >> > > >> >> > >> >> >> >> >> >>https://gist.github.com/xiaotao183/53e1bf191c1a4d030a25#file-oome-excepti >> >>o >> >> > > >n-L1 >> >> > > > >> >> > > >I started up mirror maker with 1G memory and 256M producer >>buffer. >> >>I >> >> > used >> >> > > >eclipse MAT to analyze the heap dump and found out the retained >> >>heap >> >> > size >> >> > > >of all RecordBatch objects were more than 500MB half of which >>were >> >> used >> >> > to >> >> > > >retain data that were to send to destination broker which makes >> >>sense >> >> to >> >> > > >me >> >> > > >as it is close to 256MB producer buffer but the other half of >>which >> >> were >> >> > > >used by kafka.tools.MirrorMaker$MirrorMakerProducerCallback. As >> >>every >> >> > > >producer callback in mirror maker takes the message value and >>hold >> >>it >> >> > > >until >> >> > > >the message is successfully delivered. In my case since the >> >> destination >> >> > > >broker was very unresponsive the message value held by callback >> >>would >> >> > stay >> >> > > >forever which I think is a waste and it is a major contributor >>to >> >>the >> >> > OOME >> >> > > >issue. screenshot of MAT >> >> > > > >> >> > > >> >> > >> >> >> >> >> >>https://gist.github.com/xiaotao183/53e1bf191c1a4d030a25#file-mat-screensh >> >>o >> >> > > >t-png >> >> > > > >> >> > > >The other interesting problem I observed is that when I turned >>on >> >> > > >unreachable object parsing in MAT more than 400MB memory was >> >>occupied >> >> by >> >> > > >unreachable objects. It surprised me that gc didn't clean them >>up >> >> before >> >> > > >OOME was thrown. As suggested in gc log >> >> > > > >> >> > > >> >> > >> >> >> >> >> >>https://gist.github.com/xiaotao183/53e1bf191c1a4d030a25#file-oome-gc-log- >> >>L >> >> > > >1 >> >> > > >Full GC was unable to reclaim any memory and when facing OOME >>these >> >> > > >unreachable objects should have been cleaned up. so either >>eclipse >> >>MAT >> >> > has >> >> > > >issue parsing the heap dump or there is hidden memory leak that >>is >> >> hard >> >> > to >> >> > > >find. I attached the sample screenshot of the unreachable >>objects >> >>here >> >> > > > >> >> > > >> >> > >> >> >> >> >> >>https://gist.github.com/xiaotao183/53e1bf191c1a4d030a25#file-unreachable- >> >>o >> >> > > >bjects-png >> >> > > > >> >> > > >The consumer properties >> >> > > > >> >> > > >zookeeper.connect=zk >> >> > > >zookeeper.connection.timeout.ms=1000000 >> >> > > >group.id=mm >> >> > > >auto.offset.reset=smallest >> >> > > >partition.assignment.strategy=roundrobin >> >> > > > >> >> > > >The producer properties >> >> > > > >> >> > > >bootstrap.servers=brokers >> >> > > >client.id=mirror-producer >> >> > > >producer.type=async >> >> > > >compression.codec=none >> >> > > >serializer.class=kafka.serializer.DefaultEncoder >> >> > > >> >> >> >>>>>key.serializer=org.apache.kafka.common.serialization.ByteArraySerializ >>>>>er >> >> > > >> >> > >> >> >> >>>>>value.serializer=org.apache.kafka.common.serialization.ByteArraySerial >>>>>iz >> >>>er >> >> > > >buffer.memory=268435456 >> >> > > >batch.size=1048576 >> >> > > >max.request.size=5242880 >> >> > > >send.buffer.bytes=1048576 >> >> > > > >> >> > > >The java command to start mirror maker >> >> > > >java -Xmx1024M -Xms512M -XX:+HeapDumpOnOutOfMemoryError >> >> > > >-XX:HeapDumpPath=/home/kafka/slc-phx-mm-cg.hprof >> >> > > >-XX:+PrintTenuringDistribution -XX:MaxTenuringThreshold=3 >>-server >> >> > > >-XX:+UseParNewGC -XX:+UseConcMarkSweepGC >> >>-XX:+CMSClassUnloadingEnabled >> >> > > >-XX:+CMSScavengeBeforeRemark -XX:+DisableExplicitGC >> >> > > >-Djava.awt.headless=true >> >> > > >-Xloggc:/var/log/kafka/kafka-phx/cg/mirrormaker-gc.log >>-verbose:gc >> >> > > >-XX:+PrintGCDetails -XX:+PrintGCDateStamps >>-XX:+PrintGCTimeStamps >> >> > > >-XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 >> >> > > >-XX:GCLogFileSize=10M -Dcom.sun.management.jmxremote >> >> > > >-Dcom.sun.management.jmxremote.authenticate=false >> >> > > >-Dcom.sun.management.jmxremote.ssl=false >> >> > > >-Dkafka.logs.dir=/var/log/kafka/kafka-phx/cg >> >> > > >> >> > >> >> >> >>>-Dlog4j.configuration=file:/usr/share/kafka/bin/../config/ >> tools-log4j.pr >> >>>op >> >> > > >erties >> >> > > >-cp libs/* kafka.tools.MirrorMaker --consumer.config >> >> > > >consumer.properties --num.streams 10 --producer.config >> >> > > >producer.properties --whitelist test.* >> >> > > >> >> > > >> >> > >> >> >> >> >> >> >> >> -- >> >> -- Guozhang >> >> >> >>
