Apache Accumulo 2.1.5

08 Jul 2026

About

Apache Accumulo 2.1.5 is a patch release of the 2.1 LTM line. It contains bug fixes and minor enhancements. This version supersedes earlier 2.1 releases and users upgrading to 2.1 should upgrade directly to this version instead of any prior 2.1 release.

Notable Changes

  • #5998 Added the table.shuffle.sources property that allows users to specify whether or not RFiles should be shuffled when reading from a Tablet to try and reduce the number of scan threads that are waiting on the same file to opened.
  • #6040 #6075 Prior to 2.1.5 iterators that had the same priority would execute in a non-deterministic order. In 2.1.5 the iterators with the same priority will execute in the lexicographical order of the name property.
  • #6146 Added the sserver.scan.allowed.tables.group. Scan Server property prefix that allows user to control which tables are allowed to be used with Scan Servers.
  • #6156 Scan Servers can now be used to scan offline tables.
  • #6160 Accumulo 2.1.5 requires JDK 21 to build. For runtime the minimum required JDK version is 11.
  • #5982 Adds function for bulk V2 to compute load plans based on the minimum and maximum row present within the RFile when splits are not present.
  • #5974 Caches the log recovery decision to avoid redundant work in manager for log recovery.
  • #4096 Updates the createTable command to accept a property file on inital table creation via the propFile option.
  • #6416 Removes the gc.remove.in.use.candidates experimental feature flag property enabling the behavior added in #3738
  • #6219 Adds the property manager.table.delete.optimization which will skip the delete table optimization
  • #6049 Adds the property manager.tservers.halt.grace.period which defines the time duration before the Manager halts non-responsive tservers via lock removal.

Notable Bug Fixes

  • #5856 Modified Shell to stop removing backslash characters.
  • #5888 Fail the accumulo upgrade --prepare command when table properties are set in the site configuration.
  • #5960 Fixed a bug when table.file.ec property set to inherit.
  • #5963 Enable reloading of the general.server.iter.opts.compression property so that changes don’t require process restart.
  • #5989 Adds a new log message in the Compaction Coordinator that will periodically log summary information to include number of compactions running for each table, the number of compactor, queued compactions (max 100), and running compactions for each compaction queue.
  • #6148 Fixed shell commands grep and deletemany to honor the context classloader option.
  • #6397 Fixes monitor to always show the Dead Tablet Servers table
  • #6012 Changes createTable command options to simplify table property behavior.
  • #5937 Switched to using rendezvous hashing for scan server selection.
  • #6307 Fixes multiple problems with scan timeout.

Other Improvements

  • #6029 Modified Monitor tables to support ‘all’ size option.
  • #5928 Converted Scan Servers to use Rendezvous hashing to reduce churn during scan server selection when adding or removing scan servers.
  • #5983 Added -v option to shell getsplits command to print split information that matches the supplied obfuscated extent.
  • #6005 Added compaction output tmp file name to pre-compaction log message.
  • #6014 Modified Fate to exit normally when Manager shut down instead of failing the transaction.
  • #6051 shell fate --delete command will remove the fate transaction id from the table_locks directory in ZooKeeper to match the delete behavior of the admin fate --delete command.
  • #6064 Updated log4j dependency to version 2.25.3.
  • #6067 Fixed accumulo-cluster prune bug with Scan Servers.
  • #6437 Adds –dry-run option to Merge command.
  • #6097 Only initializes vfs when deprecated prop is set.
  • #6051 Fixes the shell fate delete command.

Requirements

Accumulo 2.1.5 now requires JDK 21 to build, but still supports Java 11 runtime.

Upgrading

View the Upgrading Accumulo documentation for guidance.

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