Done. https://issues.apache.org/jira/browse/KAFKA-7660 br, Patrik
On Mon, 19 Nov 2018 at 02:03, Guozhang Wang <wangg...@gmail.com> wrote: > Hello Patrik, > > Could you file a JIRA for your findings? Also what Kafka versions are you > using (could you add that to the ticket as well)? > > Could you provide some more elaborations on what you did the JVM analysis, > so that I can try to re-produce the observations. > > > Guozhang > > On Thu, Oct 25, 2018 at 2:50 AM Patrik Kleindl <pklei...@gmail.com> wrote: > > > Hello > > > > During the analysis of JVM memory two possible issues were shown which I > > would like to bring to your attention: > > 1) Duplicate strings > > Top findings: > > string_content="stream-processor-node-metrics" count="534,277" > > string_content="processor-node-id" count="148,437" > > string_content="stream-rocksdb-state-metrics" count="41,832" > > string_content="punctuate-latency-avg" count="29,681" > > > > "stream-processor-node-metrics" seems to be used in Sensors.java as a > > literal and not interned. > > > > 2) The HashMap parentSensors > > from > > > org.apache.kafka.streams.processor.internals.StreamThread$StreamsMetricsThreadImpl > > was reported multiple times as suspicious for potentially keeping alive a > > lot of objects. In our case the reported size was 40-50MB each. > > I haven't looked too deep in the code but noticed that the class > > Sensor.java which is used as a key in the HashMap does not implement > equals > > or hashCode method. Not sure this is a problem though. > > > > Maybe someone can shed some light on this > > > > best regards > > > > Patrik > > > > > -- > -- Guozhang >