[ https://issues.apache.org/jira/browse/CASSANDRA-15796?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Paulo Motta updated CASSANDRA-15796: ------------------------------------ Bug Category: Parent values: Correctness(12982) Complexity: Normal Discovered By: User Report Severity: Normal Status: Open (was: Triage Needed) > Cassandra get range slice got Inaccurate estimates for concurrencyFactor > ------------------------------------------------------------------------- > > Key: CASSANDRA-15796 > URL: https://issues.apache.org/jira/browse/CASSANDRA-15796 > Project: Cassandra > Issue Type: Bug > Components: Legacy/Coordination > Reporter: maxwellguo > Priority: Normal > > Cassandra version :3.11.4 > For table that do not got a regular column , when we do partition range read > and we got to the code function : > {code:java} > // Some comments here > public String getRangeSlice(PartitionRangeReadCommand command, > ConsistencyLevel consistencyLevel, long queryStartNanoTime) > {code} > we will do some calculation to estimate the data per range in the function : > {code:java} > // Some comments here > private static float estimateResultsPerRange(PartitionRangeReadCommand > command, Keyspace keyspace) > {code} > when we got no index so we will use : > {code:java} > // Some comments here > command.limits().estimateTotalResults(cfs) > --->(for CQLlimits) > *public float estimateTotalResults(ColumnFamilyStore cfs) > { > // TODO: we should start storing stats on the number of rows > (instead of the number of cells, which > // is what getMeanColumns returns) > float rowsPerPartition = ((float) cfs.getMeanColumns()) / > cfs.metadata.partitionColumns().regulars.size(); > return rowsPerPartition * (cfs.estimateKeys()); > }* > {code} > when the regulars is zero ,we will got an error result that is non-zero > value divided by zero . -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org