Description of problem:

The elasticsearch container running on the OpenShift nodes generates defunc processes which slightly increases the CPU load.

Defunc processes:

1000790+ 42255 0.0 0.0 0 0 ? - Jan12 0:00 [init.sh] <defunct>
1000790+ 42138 0.0 0.0 0 0 ? - Jan12 0:00 [init.sh] <defunct>

Parent PID of above said processes is below:

4 S 1000790+ 41221 40997 41221 0 29 80 0 - 3042998 futex_ 07:24 ? 00:00:00 /usr/lib/jvm/jre/bin/java -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -Des.networkaddress.cache.ttl=60 -Des.networkaddress.cache.negative.ttl=10 -XX:+AlwaysPreTouch -Xss1m -Djava.awt.headless=true -Dfile.encoding=UTF-8 -Djna.nosys=true -XX:-OmitStackTraceInFastThrow -Dio.netty.noUnsafe=true -Dio.netty.noKeySetOptimization=true -Dio.netty.recycler.maxCapacityPerThread=0 -Dlog4j.shutdownHookEnabled=false -Dlog4j2.disable.jmx=true -Djava.io.tmpdir=/tmp/elasticsearch-10372601540569413428 -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=data -XX:ErrorFile=logs/hs_err_pid%p.log -Djava.locale.providers=COMPAT -XX:+UnlockExperimentalVMOptions -XX:MaxRAMFraction=2 -XX:InitialRAMFraction=2 -XX:MinRAMFraction=2 -Xms8192m -Xmx8192m -XX:HeapDumpPath=/elasticsearch/persistent/heapdump.hprof -Xlog:gc*,gc+age=trace,safepoint:file=/elasticsearch/persistent/elasticsearch/logs/gc.log:utctime,pid,tags:filecount=8,filesize=64m -XX:ErrorFile=/elasticsearch/persistent/elasticsearch/logs/error.log -Djdk.tls.ephemeralDHKeySize=2048 -Des.cgroups.hierarchy.override=/ -Dlog4j2.configurationFile=/usr/share/java/elasticsearch/config/log4j2.properties -Des.path.home=/usr/share/elasticsearch -Des.path.conf=/etc/elasticsearch -Des.distribution.flavor=oss -Des.distribution.type=zip -cp /usr/share/elasticsearch/lib/* org.elasticsearch.bootstrap.Elasticsearch

And finally the java processes is associated with below process (prarent PID of above said process):

1 S root 40997 1 40997 0 2 80 0 - 21960 poll_s 07:24 ? 00:00:00 /usr/bin/conmon -b /run/containers/storage/overlay-containers/0e84e2e7bd9a0d88e93b7ffb8f5dfeba068d300b78b8de476717c8a2a084092d/userdata -c 0e84e2e7bd9a0d88e93b7ffb8f5dfeba068d300b78b8de476717c8a2a084092d --exit-dir /var/run/crio/exits -l /var/log/pods/openshift-logging_elasticsearch-cdm-ra8g7a59-2-86d87b9884-hw7qh_35b74ed9-edbf-44ae-908d-4f344c33cda2/elasticsearch/0.log --log-level info -n k8s_elasticsearch_elasticsearch-cdm-ra8g7a59-2-86d87b9884-hw7qh_openshift-logging_35b74ed9-edbf-44ae-908d-4f344c33cda2_0 -P /run/containers/storage/overlay-containers/0e84e2e7bd9a0d88e93b7ffb8f5dfeba068d300b78b8de476717c8a2a084092d/userdata/conmon-pidfile -p /run/containers/storage/overlay-containers/0e84e2e7bd9a0d88e93b7ffb8f5dfeba068d300b78b8de476717c8a2a084092d/userdata/pidfile --persist-dir /var/lib/containers/storage/overlay-containers/0e84e2e7bd9a0d88e93b7ffb8f5dfeba068d300b78b8de476717c8a2a084092d/userdata -r /usr/bin/runc --runtime-arg --root=/run/runc --socket-dir-path /var/run/crio -u 0e84e2e7bd9a0d88e93b7ffb8f5dfeba068d300b78b8de476717c8a2a084092d -s

Version-Release number of selected component (if applicable):

5.4.6

How reproducible:

NA

Steps to Reproduce:

3. ...

Actual results:

Defunc prcesses are generated by elasticsearch container.

Expected results:

There should not be any defunc processes.

Additional info: