After upgrading DSE from 5.1.14 to 6.7.3 we are seeing nodes are going down with lots of errors like the one below in the logs, any thoughts?
ERROR [CoreThread-0] 2019-06-25 10:15:30,519 VerbHandlers.java:77 - Unexpected error during execution of request READS.SINGLE_READ (99097935): /10.16.6.6 -> /10.16.6.4 java.lang.AssertionError: Expected valid buffer or boundary crossed at org.apache.cassandra.utils.flow.Flow$ReduceSubscriber.onError(Flow.java:1221) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlatMap.onError(FlatMap.java:133) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlatMap$FlatMapChild.onError(FlatMap.java:185) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlatMap$FlatMapChild.onError(FlatMap.java:185) at org.apache.cassandra.io.sstable.format.AsyncPartitionReader$PartitionReader.onError(AsyncPartitionReader.java:365)
[UPDATE] Thank you @Erick Ramirez. That was (I believe) the full stack trace however we also seeing the errors you mentioned (`o.a.c.utils.memory.buffers.TemporaryBufferPool `)
ERROR [CompactionExecutor:1557] 2019-06-27 10:02:45,022 CassandraDaemon.java:126 - Exception in thread Thread[CompactionExecutor:1557,5,main] java.lang.AssertionError: Slab should have been unreferenced and all buffers returned before recycling at org.apache.cassandra.utils.memory.buffers.MemorySlabWithBumpPtr.recycle(MemorySlabWithBumpPtr.java:174) at org.apache.cassandra.utils.memory.buffers.TemporaryBufferPool.newSlab(TemporaryBufferPool.java:321) at org.apache.cassandra.utils.memory.buffers.TemporaryBufferPool.switchSharedSlab(TemporaryBufferPool.java:232) at org.apache.cassandra.utils.memory.buffers.TemporaryBufferPool.allocateFromShared(TemporaryBufferPool.java:197) at org.apache.cassandra.utils.memory.buffers.TemporaryBufferPool.allocate(TemporaryBufferPool.java:128) at org.apache.cassandra.io.util.ChunkReader.readScattered(ChunkReader.java:103) at org.apache.cassandra.cache.ChunkCacheImpl$MultiBufferChunk.asyncLoad(ChunkCacheImpl.java:215) at org.apache.cassandra.cache.ChunkCacheImpl.asyncLoad(ChunkCacheImpl.java:357) at org.apache.cassandra.cache.ChunkCacheImpl.asyncLoad(ChunkCacheImpl.java:56) at com.github.benmanes.caffeine.cache.LocalAsyncLoadingCache.lambda$get$2(LocalAsyncLoadingCache.java:129) at com.github.benmanes.caffeine.cache.BoundedLocalCache.lambda$doComputeIfAbsent$14(BoundedLocalCache.java:2039) at java.util.concurrent.ConcurrentHashMap.compute(ConcurrentHashMap.java:1853) at com.github.benmanes.caffeine.cache.BoundedLocalCache.doComputeIfAbsent(BoundedLocalCache.java:2037) at com.github.benmanes.caffeine.cache.BoundedLocalCache.computeIfAbsent(BoundedLocalCache.java:2020) at com.github.benmanes.caffeine.cache.LocalAsyncLoadingCache.get(LocalAsyncLoadingCache.java:128)
as well as `OutOfMemory` errors (on different cluster)
ERROR [CoreThread-0] 2019-06-27 14:06:15,140 VerbHandlers.java:77 - Unexpected error during execution of request READS.SINGLE_READ (330386123): /10.17.6.5 -> /10.17.6.5 java.lang.OutOfMemoryError: Direct buffer memory at org.apache.cassandra.utils.flow.Flow$ReduceSubscriber.onError(Flow.java:1221) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlatMap.onError(FlatMap.java:133) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlowTransformBase.onError(FlowTransformBase.java:38) at org.apache.cassandra.utils.flow.FlatMap.onError(FlatMap.java:133) at org.apache.cassandra.utils.flow.FlatMap$FlatMapChild.onError(FlatMap.java:185) at org.apache.cassandra.utils.flow.FlatMap$FlatMapChild.onError(FlatMap.java:185) at org.apache.cassandra.io.sstable.format.AsyncPartitionReader$PartitionReader.onError(AsyncPartitionReader.java:365)