hazelcast/hazelcast v4.1.10 on GitHub

This document lists the new features, enhancements, fixed issues and, removed or deprecated features for Hazelcast IMDG 4.1.z releases. The numbers in the square brackets refer to the issues in Hazelcast's GitHub repositories.

==== 4.1.10 ====

Enhancements

Improved connection handling. #21644
To decrease the load on the Management Center for large clusters, the level of network related metrics has been changed to DEBUG. When you need these metrics, you can use the hazelcast.metrics.debug.enabled property. #21260

Fixes

Fixed an issue where replication over WAN was failing on the source cluster members, when there are multiple batch publishers configured in a single WAN replication. #22498
Fixed an issue where the cluster was failing to operate since the indexes on backup partitions were removed by map.ClearBackupOperation. #22305
Fixed an issue where a cluster could not be formed when security is enabled, various client permissions are set, and multiple members are started simultaneously. #21507

==== 4.1.9 ====

Enhancements

Enabled XXE (XML External Entity Reference) protection for XMLInputFactory. The related issue was reported through https://huntr.dev/bounties/d63972a2-b910-480a-a86b-d1f75d24d563/. #20943

Fixes

Fixed an issue where a cluster was unresponsive when you perform a health check to see the members are in the safe state; cluster members were hanging in the REPLICA_NOT_SYNC state during such health checks. #21205
Fixed an issue where the list of members in the cluster was reset to an empty list when member IDs change after a cluster restart: this was causing startup failures since Hazelcast could not manage the events due to the empty member list after a restart. #21181
Fixed an issue where the statistics like puts and removals were not increasing when these operations are executed through Transactional interface. #21100
Fixed an issue where Hazelcast clients, which have only the IP address of a member to connect (but the member also has a hostname), were not able to connect to the cluster. #20632

==== 4.1.8 ====

For the distributions packages of IMDG, we updated the vulnerable version of log4j2 in Management Center to 2.17.0. No changes were made to the IMDG code.

==== 4.1.7 ====

For the distributions packages of IMDG, we updated the vulnerable version of log4j2 in Management Center to 2.15.0. No changes were made to the IMDG code.

==== 4.1.6 ====

Enhancements

Improved the log message that is displayed when using the hazelcast.io.selectorMode property to decrease the high CPU usage. The previous misleading message read as "Recreated Selector because of possible java/network stack bug". It has been changed to "Selector was rebuilt, consider updating Java and/or your network stack drivers". #19761
Introduced the hazelcast.internal.map.expired.key.scan.timeout.nanos property to limit the execution time of the cleanup operations, i.e., entry expiration tasks of a map; this is to prevent the increased CPU usage as the partition size grows. #19663

Fixes

Hazelcast was executing cluster wide operations when you query the state of a member using the health check endpoint - it was causing to kill all the members in a cluster; this issue has been fixed. #19837
The increment command (incr) in the Memcache client was returning the ASCII code of the expected result; this interpretation issue has been fixed. #19681

==== 4.1.5 ====

Fixes

Fixed an issue where a high amount of garbage collection pressure was occurring during repartitioning especially when having a high partition count. #19295
Fixed an issue where the client state listener was not properly working with failover clients (in blue-green deployments); it was failing with invalid configuration exception. #19116

Deprecated/Removed Features

Deprecated the following properties:
** hazelcast.client.statistics.period.seconds
** hazelcast.client.statistics.enabled
#19234

==== 4.1.4 ====

Fixes

Fixed an issue where the updates made to a persistent map store might be lost when the write coalescing is enabled. #18924
Fixed an issue where the maximum size policy for a map was being ignored when the policy is PER_NODE and the cluster is scaled down (due to losing or killing a member). #18871
Fixed an issue where the map’s Near Cache was setting its maximum size as 10.000 even if the configured eviction policy is NONE. #18834
The LRU eviction policy now takes last access time value into account to prevent premature removal of the lately added but not yet accessed map entries. #18632

==== 4.1.3 ====

Enhancements

Introduced a new mechanism in the background expiration tasks; now a thread local array controls the allocations for these tasks otherwise which may cause increased garbage collection pressure and CPU usage spikes when you use aggressive expiration configurations, e.g., low time-to-live values. #18480
Updated the Hazelcast Kubernetes plugin dependency version to 2.2.2. #18331
Added the ability to register the class definition of the parent generic record and check the class definition compatibility for nested portable fields. #18284

Fixes

The difference between the Near Cache configurations before and after a client is recreated with the same client failover configuration is fixed now. #18361
The eviction of the idle entries is now stable in IMDG 4.x series by aligning the behaviors of index-scan and full-scan in maps. #18346
The IllegalArgumentException is not thrown anymore when there is Near Cache configured for both the member and client sides for the same map and serialize-keys option is false. #18313

==== 4.1.2 ====

Fixes

Fixed an issue where the Java client was not receiving membership events when a member with Hot Restart Persistence is restarted. #18268
Fixed an issue where the Near Cache configuration of a map in client was not the same after the client is recreated with the same client failover configuration. #18356
Fixed an issue that prohibited Hazelcast from being used as Tomcat session manager when it is also deployed in a web application context: When a client application that uses Hazelcast tries to connect to the Hazelcast cluster and this application’s web sessions are persisted using Hazelcast’s Tomcat session manager, the session manager could not connect to the cluster. This has been fixed by improving Hazelcast’s service loader mechanism. #18116
Fixed an issue where the metrics for map hits statistics in Management Center were decreasing as the map entries are being expired. #18112
When the in-memory format of a map is NATIVE and the uploaded user code has missing classes (in case the user code deployment feature is used), the resulting exception could not be seen on the client side when a map query is run. This was causing the client to hang indefinitely and fixed by improving the failure handling for this case. #18084
Fixed an issue where the queue items were being delivered more than once when they are reproduced after a member leaves the cluster. #18057
When the user code deployment is used and the classes to be deployed have com.hazelcast prefix, it was causing failures in other Hazelcast products, e.g., Jet. This has been fixed by making use of the context classloader when loading such classes. #17915
The -c parameter of the cp-subsystem.sh script was used for both cluster name and group variables. This has been fixed by introducing the -g parameter for groups. #17907
Fixed an issue where the remove() and delete() operations of maps were not updating the local map statistics. #17750

==== 4.1.1 ====

New Features

Node Aware Partition Grouping: Added the support of partition grouping mechanism in the Hazelcast discovery plugin for Kubernetes. You can create partition groups according to the name of the node which is provided by this plugin and on which the containers/pods run. See the NODE_AWARE section of the IMDG Reference Manual for more information.

Enhancements

Introduced a configuration property to ignore errors during enabling the XXE protection. This protection works with JAXP 1.5 (Java 7 Update 40) and newer. When an older JAXP implementation is added to the classpath, e.g., Xerces and Xalan, an exception is thrown. The newly introduced property, namely hazelcast.ignoreXxeProtectionFailures, allows you to ignore those exceptions. See the System Properties appendix of the IMDG Reference Manual for more information.
Updated the Hazelcast Kubernetes plugin dependency to 2.2.1. #17928
Separated the hazelcast-sql Maven module into hazelcast-sql-core and hazelcast-sql. #17922
Implemented the IMap.entrySet() method for the partition ID set. #17886

Fixes

Fixed an issue where the clients were opening two connections to the same member when the member is behind a private network. #17888
Fixed an issue where the Javadoc of release methods for session-aware semaphore structure was incorrectly addressing "threads" instead of "Hazelcast instances". #17827
Fixed an issue where the Hazelcast Java client was not able to resolve the new address of a restarted member, e.g., for a setup in Docker environment. #17062

==== 4.1 ====

New Features

Hazelcast IMDG Open Source New Features:

SQL Implementation: Implemented the SQL engine that supports map scans, index scans, projections and filters. It also introduces the hazelcast-sql module to handle the SQL engine’s dependencies on Apache Calcite. See the SQL section.
Automatic Discovery Strategy Detection: Hazelcast now automatically detects the cloud environment it’s running on (Kubernetes, AWS, GCP or Azure) and applies the necessary discovery strategy for the environment. This allows automatically forming the Hazelcast clusters in cloud environments without any configuration. See the Auto Detection section.
Overriding Configuration: You can now override the configuration entries of your cluster without changing the declarative configuration files (XML/YAML). See the Overriding Configuration section.
Instance Tracking: Hazelcast now writes a file on a Hazelcast member startup at the configured location. This file contains metadata about the member such as version, product name and process ID, and it is not deleted on the member shutdown. See the Instance Tracking section.

Hazelcast IMDG Enterprise New Features:

Security Audit Logging: This feature allows observing some important cluster events. Auditable events have a unique type ID, and contain a timestamp and importance level. See the Logging Auditable Events section.

Breaking Changes

Starting a standalone Hazelcast instance requires disabling Auto Detection joiner (before it required disabling Multicast joiner). #17112
In a CP subsystem session, a generic IllegalStateException was being thrown when Hazelcast is shutdown. Now the same situation throws HazelcastInstanceNotActiveException. #17120
Implemented and/or overridden the default methods in Java 8 collections, such as computeIfAbsent(), forEach() compute() and replaceAll() for maps. #14913

Enhancements

Hazelcast IMDG Open Source Enhancements:

Improvements in Partial Network Disconnections: Introduced properties to be configured to detect and resolve the partial network issues among the Hazelcast IMDG members. See #16680 and the Partial Network Partitions section.
Parallel Independent Migrations: Parallelized the partition replica migrations so that the time needed for rebalancing the partitions after adding or removing a member to/from a cluster is reduced. See the hazelcast.partition.max.parallel.migrations property explanation in the System Properties appendix.
CP Subsystem Listeners and Metrics: Added membership and group availability listeners for CP Subsystem. Also, added support for publishing CP Subsystem and CP data structure statistics via Metrics. See the CP Subsystem Listeners section.
GenericRecord: Added support for accessing domain objects without domain classes. See the GenericRecord section.
Thread Affinity: Introduced the CPU thread affinity; threads can have affinity for particular CPUs and using this you have a better control on the latency and a better throughput. See the CPU Thread Affinity section.
Trusted Interfaces: It is now possible to restrict the source IP addresses from which the Management Center operations are allowed. See the Limiting Source Addresses section.
Priority Queue: Added support for the queues with comparators. Using Priority Queue, you can define items with higher priority to be polled first. See the Priority Queue section.
Statistics for Durable and Scheduled Executor Services: Added the statistics for scheduled and durable executor services, and for the executor of offloaded entry processors to be monitored by Management Center.

Hazelcast IMDG Enterprise Enhancements:

Out-of-the-Box Kerberos Support: Introduced support for Kerberos authentication protocol which is one of the standard solutions for single-sign-on. It also adds the GSSAPI authentication support in LDAP configuration. See the Kerberos Authentication Type section.
Multiple Persistent Directories: Added support for multiple mounting directories in the persistent memory configuration and also thread affinity for NVMs (Non-Volatile Main Memories). See the Using Persistent Memory section.
WAN Throttling Mechanism: This prevents the WAN consumers from getting overloaded by the WAN producers if transferring the WAN events takes less time than processing them in the target cluster. This can be the case with WAN synchronization if the network latency is low enough. It can be configured using the following properties:
** hazelcast.wan.consumer.invocation.threshold
** hazelcast.wan.consumer.ack.delay.backoff.init
** hazelcast.wan.consumer.ack.delay.backoff.max
** hazelcast.wan.consumer.ack.delay.backoff.multiplier
#17113
Implemented a new concurrent High-Density Memory Store index for the queries, based on B+ tree that is enabled by default; brings better performance for lookup queries and enables SQL queries.

The following are the other improvements performed to solve the enhancement issues opened by the Hazelcast customers/team.

Added the missing replicatedmap-permission support to the XML and YAML configuration handlers. #17812
Replaced the word "should" with "must" in the exception messages to improve the user focus and indicate obligation rather than advice. #17710
Added the getAndDecrement() operation support for the IAtomicLong data structure. #17699
Introduced the mode configuration attribute for the persistent memory. It defines operational mode of it which can be either MOUNTED or SYSTEM_MEMORY. #17696
Added the support for checking duplicate fields when building class definitions. #17682
Added the support for IList with nullable items to the client protocol. #17690
Improved the robustness of the diagnostics log writer and its plugins. #17665
Added the client name tag to the client related metrics. #17654
Added a check for IMap READ permissions for the maps involved in the SQL query executions. #17612
Added the support for accessing the Hazelcast instance in the login modules and credential factories. #17605
Introduced a simplified configuration of Kerberos authentication for simple scenarios. #17573
Added statistics support for IBM, OpenJ9, ZGC and Shenandoah. #17561
Introduced a state-tracking mechanism for the external configuration parser; all mismatched/unapplied configuration entries coming from environment variables or system properties are now logged. #17559
Updated the jackson.version to 2.11.2 and SnakeYAML to 2.1. #17484, #17446
Added support for the merge operation in IMap. #17419
Added public classes to expose the member- and client-side caching provider implementations (in the JCache implementation) without referring to internal classes. #17320
Improved the entry processing mechanism so that the read-only processors on backups are not executed anymore. #17318
Improved CacheSimpleConfig so that it now accepts cache name in its constructors. #17287
Cleaned up the noisy initial log messages on Hazelcast startups. #17243
Introduced auto-disposable tasks for the scheduled executor service. #17215
Added client labels to ClientEndpointImpl.toString() to simplify the client identification (in addition to client uuid) on the Hazelcast member side. #17178
Added exception handling when creating caches with tenant control. #17122
Added support for IMap.compute(). #17030
Added support to allow submitting and executing operations while a member is shutting down to increase the availability of a cluster more that keeps large data. #17028
Added ExtendedMapEntry in order to create a mechanism for setting TTLs in entry processors. #16991
Added hazelcast-azure discovery plugin to the hazelcast-all module. #16982
Introduced the ConfigRecognition API that determines if a provided declarative configuration is recognized by the rules defined in a given implementation. Along with the API the following three implementations are added:
** MemberConfigRecognizer for recognizing member XML and YAML configurations
** ClientConfigRecognizer for recognizing client XML and YAML configurations
** ClientFailoverConfigRecognizer for recognizing failover client XML and YAML configurations
#16958
Added the publishAll(), publishAllAsync() and publishAsync() methods to ITopic. #16946
Made the diagnostics logs cloud-friendly so that they can also be sent to stdout in addition to sending to local files. #16941
Improved the mechanism of partition table updates to eliminate the latencies when these updates are sent to the clients by a member. #16939
Improved the client configuration such that when the client failover configuration is provided, the reconnect mode cannot be set as off; it now fails fast in this case. #16886
Introduced the forEach() loop support for IMap. #16877
Added the load() method to Config, ClientConfig and ClientFailoverConfig classes. This method loads the configuration with the known locations. If not found, the default configuration is returned. #16864
Improved the deleteAll() (MapStore) and ITopic Javadocs. #16862, #16861,
Added support for IMap.computeIfAbsent(). #16808
Added the setAll() and setAllAsync() methods for IMap. #16787
Added the creation time metric for the executor service. #16775
Improved an unclear exception message for credentials. #16756
Updated the related aspects of Hazelcast IMDG after the changes done on the client protocol side to add the ability to add new parameters, methods, services, events and custom types to codecs. #16718
Introduced the putAllAsync() method for MultiMap. #16698
Defined metrics for ISet and IList collections. #16665
Upgraded log4j2 version to 2.13.0. #16654
Improved the computeIfPresent() implementation so that now it keeps a clone of the old/existing value and uses that for replace/delete operations. #16636
Introduced the hazelcast.logging.details.enabled property to make the logging of cluster version, name and IP optional to decrease the noise in the logs when, for example, you have a single-member cluster. #16622
Upgraded the Hazelcast Kubernetes plugin version to 2.0.1. #16590
Added the support for automatically detecting the classloader of a type for the user code deployment feature. #16585
Made IMap.putAllAsync() and IMap.submitToKeys() methods public API. #16449
Clarified the exception message when you connect to a cluster with an invalid cluster name. #15099
Refactored the check and retry initialization logic of ReplicatedMapProxy so that they are performed in parallel for different partitions. #14331
Improved the behavior of ConcurrentMap.computeIfPresent: combined single client-server round trips instead of two (for get and replace methods). #11958

Fixes

Fixed an exception in the /node-state REST calls when the member is not fully activated. #17798
Fixed an issue where Hazelcast was not releasing the acquired lock sessions that fail for the reasons other than session expiration and wait key cancellation. #17697
Fixed an issue where Hazelcast was returning false if a client is successfully deregistered from any member, but events are still delivered for the non-deregistered ones. #17646
Fixed a data loss issue that was happening while promoting a lite member to a data member. #17621
Fixed an issue where the configuration was not updating entries' time-to-live values if the entry processor implements the Offloadable interface. #17606
Fixed an issue where the caller stacktrace was missing on the rethrown async runtime exceptions. #17546
Fixed the rendering of diagnostics in case there is an exception inside a diagnostics plugin. #17501
Fixed an exception that is thrown when using the entry store API and issuing a put into the IMap for an item which is not in the map but exists in the backing store. #17441
Fixed an issue where the custom load balancers could not be configured declaratively. #17415
Fixed a race issue when creating a cache (JCache) using multiple methods with the same cache name but having different keys. #17286
Fixed an issue where the repeated calls of executeOnKeys() in Hazelcast clients for NATIVE maps was causing a continuous increase in the used memory and exhaustion of the memory pool after a while. #17276
Fixed an issue where ReliableTopicMessageListener was firing a warning when the client is shutting down. #17153
Fixed an issue where the client was stuck with an outdated member list after a split-brain scenario. #17147
Fixed the member side user code deployment; it was throwing an exception when inner classes are used to be loaded. #17044
Fixed the broken interoperability between the CompletableFuture methods. #17020
Fixed an issue where touching a map entry having an entry processor working on it was modifying its time-to-live. #16987
Fixed an issue in the cache service where its pre-join operation was considering CacheConfig as resolved: it was assuming that key/value types, user customizations and other cache configurations have been loaded. This was an issue when the cache is not touched yet. #16917
Fixed an issue where Management Center was not working as expected when the cluster is set up using advanced network configuration. #16910
Fixed an issue where ServiceLoader was round-tripping between URL and URI, and consequently loses the associated URLStreamHandler when trying to load Hazelcast from a custom class loader. #16846
Fixed an issue where the class definitions, that are registered explicitly in the serialization configuration and have the same class ID in different factories, were not handled properly. #16831
Fixed the NullPointerException in IndexCopyBehavior.NEVER mode. #16784
Fixed an issue where the client XML configuration could not properly handle the empty Near Cache name. #16768
Fixed an issue where the client permissions for Reliable Topic and Ringbuffer were missing. #16755
Fixed an issue where the type information was missing the Metrics MBeans. #16747
Fixed an issue where the REST API was always requiring the call URLs to end with a slash character. #16688
Fixed an issue where the service URL for Eureka could not be set using the declarative configuration. #16679
Fixed an issue where the wait key of a blocking call within a Raft invocation was still being reported as a live operation, when the key times out. #16614
Fixed an issue where the upload of classes using the client user code deployment were not successful when they are retrieved not in their created order. #16612
Fixed an issue where the size() method was returning a negative value when map, cache and multimap contain more than Integer.MAX_VALUE entries. #16594
Fixed an invalidation issue when using a transactional map from a cache with a Near Cache: the cache invalidation event occurs when the transactionalMap.put method is called. As a result, the entry was getting invalidated before the change is committed to the map. #16579
Fixed an issue where InPredicate was not invoking value comparison when the read attribute is null. #15100
Fixed an issue where Map, Cache, MultiMap data structures were returning negative values (size()) when the size is more than Integer.MAX_VALUE. #14935
Fixed an issue when a Hazelcast client calls the distributed executor service and the callable throws an exception with a custom type, then the exception was not being transported to the client. #9753

Contributors

We would like to thank the contributors from our open source community who worked on this release:

Inel Pandzic
Omid Pourhadi
Ryan Lindeborg
Santhosh Kumar
Bartek Kowalczyk
Ashutosh Agrawal
Ádám Berkecz
HugeOrangeDev
Harry Tran
Stephen Russett
Ulf Adams
Abdul Aziz Ali
Dmitry Konstantinov
Anmol Chaddha
lprimak
keteracel
Burak Sezer
wangumer
Marcin L
Stefan Birkner
André Wölfing
ndeevy