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Jeff Griffith commented on CASSANDRA-11117: ------------------------------------------- the code that updates this is here in ColmnFamilyStore.java: {code} public void apply(DecoratedKey key, ColumnFamily columnFamily, SecondaryIndexManager.Updater indexer, OpOrder.Group opGroup, ReplayPosition replayPosition) { long start = System.nanoTime(); Memtable mt = data.getMemtableFor(opGroup, replayPosition); final long timeDelta = mt.put(key, columnFamily, indexer, opGroup); maybeUpdateRowCache(key); metric.samplers.get(Sampler.WRITES).addSample(key.getKey(), key.hashCode(), 1); metric.writeLatency.addNano(System.nanoTime() - start); if(timeDelta < Long.MAX_VALUE) metric.colUpdateTimeDeltaHistogram.update(timeDelta); } {code} That "if (timeDelta < Long.MAX_VALUE)" looks ill-conceived since there are no longs > max long, but i don't really know what exactly is overflowing in the histogram. > ColUpdateTimeDeltaHistogram histogram overflow > ---------------------------------------------- > > Key: CASSANDRA-11117 > URL: https://issues.apache.org/jira/browse/CASSANDRA-11117 > Project: Cassandra > Issue Type: Bug > Reporter: Chris Lohfink > Assignee: Joel Knighton > Priority: Minor > Fix For: 2.2.x, 3.0.x, 3.x > > > {code} > getting attribute Mean of > org.apache.cassandra.metrics:type=ColumnFamily,name=ColUpdateTimeDeltaHistogram > threw an exceptionjavax.management.RuntimeMBeanException: > java.lang.IllegalStateException: Unable to compute ceiling for max when > histogram overflowed > {code} > Although the fact that this histogram has 164 buckets already, I wonder if > there is something weird with the computation thats causing this to be so > large? It appears to be coming from updates to system.local > {code} > org.apache.cassandra.metrics:type=Table,keyspace=system,scope=local,name=ColUpdateTimeDeltaHistogram > {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)