To follow up on this, our specific problem was with a custom CachedSchemaRegistry. external/storm-hdfs master branch uses CachedSchemaRegistry from a Confluent dep on version 1 which also has this bug. It is fixed in later Confluent versions of confluentinc/schema-registry like this missing cache entry in 1.x: https://github.com/confluentinc/schema-registry/blob/master/client/src/main/java/io/confluent/kafka/schemaregistry/client/CachedSchemaRegistryClient.java#L152
I don't have time right now to see if storm-hdfs can bump to something newer than https://github.com/apache/storm/blob/master/external/storm-hdfs/pom.xml#L205 but will report if I do. Kris On Sun, Sep 11, 2016 at 1:31 PM, Kristopher Kane <kkane.l...@gmail.com> wrote: > This took a while as I could not get INFO logging to come out of the > serializer in Kryo. The CachedSchemaRegistry and > EnhancedCachedSchmeaRegistry - in our raw scheme deserializer (with > serialization into Avro) is 100% cache after the initial load. As you > said, the serializer with the IdentityHashMap in org.apache.storm.hdfs.avro. > ConfluentAvroSerializer.getFingerprint(ConfluentAvroSerializer.java:74) looks > to be the problem - although I couldn't get it to log the cache misses for > me in the serializer itself. > > Here is the evidence: > > This thread dump is after the topology has been running for a few > minutes. No new schemas are being introduced but still opening > 'HttpURLConnection'. The deserializer bolt says all cache requests are a > hit and are not going to the SchemaRegistry > > "Thread-3-disruptor-executor[8 8]-send-queue" - Thread t@49 > java.lang.Thread.State: RUNNABLE > at java.net.SocketInputStream.socketRead0(Native Method) > at java.net.SocketInputStream.socketRead(SocketInputStream.java:116) > at java.net.SocketInputStream.read(SocketInputStream.java:170) > at java.net.SocketInputStream.read(SocketInputStream.java:141) > at java.io.BufferedInputStream.fill(BufferedInputStream.java:246) > at java.io.BufferedInputStream.read1(BufferedInputStream.java:286) > at java.io.BufferedInputStream.read(BufferedInputStream.java:345) > - locked <670c88ea> (a java.io.BufferedInputStream) > at sun.net.www.MeteredStream.read(MeteredStream.java:134) > - locked <2a8ccb96> (a sun.net.www.http.KeepAliveStream) > at java.io.FilterInputStream.read(FilterInputStream.java:133) > at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read( > HttpURLConnection.java:3336) > at com.fasterxml.jackson.core.json.ByteSourceJsonBootstrapper. > ensureLoaded(ByteSourceJsonBootstrapper.java:503) > at com.fasterxml.jackson.core.json.ByteSourceJsonBootstrapper. > detectEncoding(ByteSourceJsonBootstrapper.java:129) > at com.fasterxml.jackson.core.json.ByteSourceJsonBootstrapper. > constructParser(ByteSourceJsonBootstrapper.java:224) > at com.fasterxml.jackson.core.JsonFactory._createParser( > JsonFactory.java:1244) > at com.fasterxml.jackson.core.JsonFactory.createParser( > JsonFactory.java:755) > at com.fasterxml.jackson.databind.ObjectMapper. > readValue(ObjectMapper.java:2199) > at io.confluent.kafka.schemaregistry.client.rest. > utils.RestUtils.httpRequest(RestUtils.java:137) > at io.confluent.kafka.schemaregistry.client.rest.utils.RestUtils. > lookUpSubjectVersion(RestUtils.java:164) > at org.apache.storm.hdfs.avro.EnhancedCachedSchemaRegistry. > getVersionFromRegistry(EnhancedCachedSchemaRegistry.java:80) > at org.apache.storm.hdfs.avro.EnhancedCachedSchemaRegistry.getVersion( > EnhancedCachedSchemaRegistry.java:176) > - locked <6b561b0f> (a org.apache.storm.hdfs.avro. > EnhancedCachedSchemaRegistry) > at org.apache.storm.hdfs.avro.ConfluentAvroSerializer.getFingerprint( > ConfluentAvroSerializer.java:74) > at org.apache.storm.hdfs.avro.AbstractAvroSerializer.write( > AbstractAvroSerializer.java:50) > at org.apache.storm.hdfs.avro.AbstractAvroSerializer.write( > AbstractAvroSerializer.java:45) > at com.esotericsoftware.kryo.Kryo.writeClassAndObject(Kryo.java:568) > at com.esotericsoftware.kryo.serializers.CollectionSerializer.write( > CollectionSerializer.java:75) > at com.esotericsoftware.kryo.serializers.CollectionSerializer.write( > CollectionSerializer.java:18) > at com.esotericsoftware.kryo.Kryo.writeObject(Kryo.java:486) > at backtype.storm.serialization.KryoValuesSerializer.serializeInto( > KryoValuesSerializer.java:44) > at backtype.storm.serialization.KryoTupleSerializer.serialize( > KryoTupleSerializer.java:44) > at backtype.storm.daemon.worker$mk_transfer_fn$transfer_fn__ > 5543.invoke(worker.clj:142) > at backtype.storm.daemon.executor$start_batch_transfer_ > _GT_worker_handler_BANG_$fn__3539.invoke(executor.clj:274) > at backtype.storm.disruptor$clojure_handler$reify__3196. > onEvent(disruptor.clj:58) > at backtype.storm.utils.DisruptorQueue.consumeBatchToCursor( > DisruptorQueue.java:125) > at backtype.storm.utils.DisruptorQueue.consumeBatchWhenAvailable( > DisruptorQueue.java:99) > at backtype.storm.disruptor$consume_batch_when_available. > invoke(disruptor.clj:80) > at backtype.storm.disruptor$consume_loop_STAR_$fn__3209. > invoke(disruptor.clj:94) > at backtype.storm.util$async_loop$fn__544.invoke(util.clj:475) > at clojure.lang.AFn.run(AFn.java:22) > at java.lang.Thread.run(Thread.java:745) > > > I've attached two screen shots of the JVisualVM CPU profilers. The one > titled 'multiple-jvm' represents a topology with two workers and high CPU > usage on RestUtil. The file title 'single-jvm' represents a topology with > one worker and no CPU usage for RestUtil. > > > I think this is pretty good evidence but I would love to know how to log > from the serializer running in Kryo as this would give me 100% proof. Can > anyone help me understand what is going on there? > > Thanks, > > Kris > > On Wed, Sep 7, 2016 at 12:11 PM, Aaron Niskodé-Dossett <doss...@gmail.com> > wrote: > >> Let us know what you find, especially if the serializer needs to be more >> defensive to ensure proper caching. >> >> On Tue, Sep 6, 2016 at 8:45 AM Kristopher Kane <kkane.l...@gmail.com> >> wrote: >> >>> Come to think of it, I did see RestUtils rank some what higher in the >>> visualvm CPU profiler but did not give it the attention it deserved. >>> >>> On Tue, Sep 6, 2016 at 9:39 AM, Aaron Niskodé-Dossett <doss...@gmail.com >>> > wrote: >>> >>>> Hi Kris, >>>> >>>> One possibility is that the Serializer isn't actually caching the >>>> schema <-> id mappings and is hitting the schema registry every time. The >>>> call to register() in getFingerprint() [1] in particular can be a finicky >>>> since the cache is ultimately in an IDENTITY hash map, not a regular old >>>> hashmap[2]. I'm familiar with the Avro deserializer you're using and >>>> though it accounted for this, but perhaps not. >>>> >>>> You could add timing information to the getFingerprint() and >>>> getSchema() calls in ConfluentAvroSerializer. If the results indicate >>>> cache misses, that's probably your culprit. >>>> >>>> Best, Aaron >>>> >>>> >>>> [1] https://github.com/apache/storm/blob/master/external/storm- >>>> hdfs/src/main/java/org/apache/storm/hdfs/avro/ConfluentAvroS >>>> erializer.java#L66 >>>> [2] https://github.com/confluentinc/schema-registry/blob/v1. >>>> 0/client/src/main/java/io/confluent/kafka/schemaregistry >>>> /client/CachedSchemaRegistryClient.java#L79 >>>> >>>> On Tue, Sep 6, 2016 at 7:40 AM Kristopher Kane <kkane.l...@gmail.com> >>>> wrote: >>>> >>>>> Hi everyone. >>>>> >>>>> I have a simple topology that uses the Avro serializer ( >>>>> https://github.com/apache/storm/blob/master/external/storm- >>>>> hdfs/src/main/java/org/apache/storm/hdfs/avro/ConfluentAvroS >>>>> erializer.java) and writes to Elasticsearch. >>>>> >>>>> The topology is like this: >>>>> >>>>> Kafka (raw scheme) -> Avro deserializer -> Elasticsearch >>>>> >>>>> This topology runs well with one worker, however, once I add one more >>>>> worker (total of two) and change nothing else, the topology throughput >>>>> drops and tuples start timing out. >>>>> >>>>> I've attached visualvm/jstatd to the workers when in multi worker mode >>>>> - and added some jmx configs to the worker opts - but I am unable to see >>>>> anything glaring. >>>>> >>>>> I've never seen Storm act this way but have also never worked with a >>>>> custom serializer so assume that it is the culprit but I cannot explain >>>>> why. >>>>> >>>>> Any pointers would be appreciated. >>>>> >>>>> Kris >>>>> >>>>> >>>>> >>>>> >>>>> >>> >
