I'm currently running into a ConcurrentModificationException ingesting data
as we attempt to upgrade from Solr 8.1 to 8.2. It's not every document, but
it definitely appears regularly in our logs. We didn't run into this
problem in 8.1, so I'm not sure what might have changed. I feel like this
is probably a bug, but if there's a workaround or if there's an idea of
something I might be doing wrong, please let me know.
Stack trace:
o.a.s.u.ErrorReportingConcurrentUpdateSolrClient Error when calling
SolrCmdDistributor$Req: cmd=add{_version=<version>,id=<id>}; node=StdNode:
https://<server>/solr/coll_shard1_replica_n2/ to
https://<server>/solr/coll_shard1_replica_n2/
=> java.util.ConcurrentModificationException
at java.util.LinkedHashMap.forEach(LinkedHashMap.java:686)
java.util.ConcurrentModificationException: null
at java.util.LinkedHashMap.forEach(LinkedHashMap.java:686)
at
org.apache.solr.common.SolrInputDocument.writeMap(SolrInputDocument.java:51)
at
org.apache.solr.common.util.JavaBinCodec.writeSolrInputDocument(JavaBinCodec.java:658)
at
org.apache.solr.common.util.JavaBinCodec.writeKnownType(JavaBinCodec.java:383)
at
org.apache.solr.common.util.JavaBinCodec.writeVal(JavaBinCodec.java:253)
at
org.apache.solr.common.util.JavaBinCodec.writeMapEntry(JavaBinCodec.java:813)
at
org.apache.solr.common.util.JavaBinCodec.writeKnownType(JavaBinCodec.java:411)
at
org.apache.solr.common.util.JavaBinCodec.writeVal(JavaBinCodec.java:253)
at
org.apache.solr.common.util.JavaBinCodec.writeIterator(JavaBinCodec.java:750)
at
org.apache.solr.common.util.JavaBinCodec.writeKnownType(JavaBinCodec.java:395)
at
org.apache.solr.common.util.JavaBinCodec.writeVal(JavaBinCodec.java:253)
at
org.apache.solr.common.util.JavaBinCodec.writeNamedList(JavaBinCodec.java:248)
at
org.apache.solr.common.util.JavaBinCodec.writeKnownType(JavaBinCodec.java:355)
at
org.apache.solr.common.util.JavaBinCodec.writeVal(JavaBinCodec.java:253)
at
org.apache.solr.common.util.JavaBinCodec.marshal(JavaBinCodec.java:167)
at
org.apache.solr.client.solrj.request.JavaBinUpdateRequestCodec.marshal(JavaBinUpdateRequestCodec.java:102)
at
org.apache.solr.client.solrj.impl.BinaryRequestWriter.write(BinaryRequestWriter.java:83)
at
org.apache.solr.client.solrj.impl.Http2SolrClient.send(Http2SolrClient.java:338)
at
org.apache.solr.client.solrj.impl.ConcurrentUpdateHttp2SolrClient$Runner.sendUpdateStream(ConcurrentUpdateHttp2SolrClient.java:231)
at
org.apache.solr.client.solrj.impl.ConcurrentUpdateHttp2SolrClient$Runner.run(ConcurrentUpdateHttp2SolrClient.java:176)
at
com.codahale.metrics.InstrumentedExecutorService$InstrumentedRunnable.run(InstrumentedExecutorService.java:181)
at
org.apache.solr.common.util.ExecutorUtil$MDCAwareThreadPoolExecutor.lambda$execute$0(ExecutorUtil
.java:209)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
