GridGain 8.9.38 Release Notes

Overview

GridGain 8.9.38 adds an optional Jetty 12 REST connector (Java 17+) and new thread-pool and client-session queue tunables.

Deprecation Notice

ignite-ml Module

Starting with this release, the ignite-ml module is deprecated and will be removed in a future release. This deprecation only affects the GridGain module, compatibility with the ignite-ml-ext Apache Ignite extension is unaffected.

TRANSACTIONAL_SNAPSHOT Atomicity Mode

Starting with this release, the TRANSACTIONAL_SNAPSHOT cache atomicity mode is deprecated and will be removed in a future release. Use the TRANSACTIONAL or ATOMIC atomicity mode instead. For more information, see the Atomicity Modes documentation.

New Features

Optional Jetty 12 REST Connector

With this release, GridGain ships a Jetty 12-based REST connector as an optional module. The connector requires Java 17 or later and is provided in addition to the default REST connector, so existing deployments continue to work unchanged. The optional module supports XML configuration and HTTPS/SSL. For details, see the Jetty 12 REST Module documentation.

Configurable Thread Pool Sizes

With this release, GridGain adds system properties that let you tune the sizes of several internal thread pools. Use them to adjust resource usage for your workload. For details, see the Thread Pool Tuning documentation.

Client Session Outbound Message Queue Limit

With this release, GridGain adds a configurable size limit for the outbound message queue of a client session. The limit bounds the amount of memory a slow or unresponsive client can cause the server to buffer. For details, see the Getting Started with Thin Clients documentation.

Improvements and Fixed Issues

Community Edition Changes

Issue ID Category Description

Issue ID	Category	Description
GG-51599	Platforms & Thin Clients	Fixed a WAL state race on enable and disable.
GG-51593	Cluster Storage Engine	Improved rebalance performance on clusters with a large number of cache groups.
GG-51592	Cluster Storage Engine	Improved exchange processing performance on clusters with a large number of caches.
GG-51582	Platforms & Thin Clients	Fixed an assertion error caused by an extra column in query results.
GG-51568	Platforms & Thin Clients	Fixed a JDBC query cancellation issue that could break further queries on the same connection.
GG-51557	Machine Learning	The `ignite-ml` module is now deprecated.
GG-51544	Cluster Transactions	The `TRANSACTIONAL_SNAPSHOT` cache atomicity mode is now deprecated.
GG-51405	Binary Objects	Enhanced affinity key resolution to better handle and resolve conflicts. Table type metadata is now automatically registered when a table is created.
GG-51404	Cluster REST API	Added a guide for migrating from Jetty 9 to Jetty 12.
GG-51403	Platforms & Thin Clients	Fixed the thin client hanging when an SSL endpoint stops responding during the handshake.
GG-51402	Platforms & Thin Clients	.NET: Thin client: fixed round-robin selection of the default socket.
GG-51277	Platforms & Thin Clients	.NET: Thin client: fixed lost exception details on retry.
GG-51276	Platforms & Thin Clients	Java thin client: fixed binary metadata being sent after reconnect.
GG-51218	Diagnostics and Failure Handling	The TDE keystore is no longer written to the persistence dump.
GG-51208	Cluster REST API	Added an optional Jetty 12 module.
GG-51100	Platforms & Thin Clients	Continuous Query: fixed doubled serialization of the `oldValue` field in REMOVE and EXPIRY events.
GG-51082	Cluster Control Script	`control.sh` commands now fail or print a warning when connected to a node running in maintenance mode.
GG-50989	Cluster Storage Engine	You can now set thread pool sizes by using the `IGNITE_*_THREAD_POOL_SIZE` system properties.
GG-50976	Platforms & Thin Clients	Added a size limit for the client-session outbound message queue.

GG-51599

Platforms & Thin Clients

Fixed a WAL state race on enable and disable.

GG-51593

Cluster Storage Engine

Improved rebalance performance on clusters with a large number of cache groups.

GG-51592

Cluster Storage Engine

Improved exchange processing performance on clusters with a large number of caches.

GG-51582

Platforms & Thin Clients

Fixed an assertion error caused by an extra column in query results.

GG-51568

Platforms & Thin Clients

Fixed a JDBC query cancellation issue that could break further queries on the same connection.

GG-51557

Machine Learning

The ignite-ml module is now deprecated.

GG-51544

Cluster Transactions

The TRANSACTIONAL_SNAPSHOT cache atomicity mode is now deprecated.

GG-51405

Binary Objects

Enhanced affinity key resolution to better handle and resolve conflicts. Table type metadata is now automatically registered when a table is created.

GG-51404

Cluster REST API

Added a guide for migrating from Jetty 9 to Jetty 12.

GG-51403

Platforms & Thin Clients

Fixed the thin client hanging when an SSL endpoint stops responding during the handshake.

GG-51402

Platforms & Thin Clients

.NET: Thin client: fixed round-robin selection of the default socket.

GG-51277

Platforms & Thin Clients

.NET: Thin client: fixed lost exception details on retry.

GG-51276

Platforms & Thin Clients

Java thin client: fixed binary metadata being sent after reconnect.

GG-51218

Diagnostics and Failure Handling

The TDE keystore is no longer written to the persistence dump.

GG-51208

Cluster REST API

Added an optional Jetty 12 module.

GG-51100

Platforms & Thin Clients

Continuous Query: fixed doubled serialization of the oldValue field in REMOVE and EXPIRY events.

GG-51082

Cluster Control Script

control.sh commands now fail or print a warning when connected to a node running in maintenance mode.

GG-50989

Cluster Storage Engine

You can now set thread pool sizes by using the IGNITE_*_THREAD_POOL_SIZE system properties.

GG-50976

Platforms & Thin Clients

Added a size limit for the client-session outbound message queue.

Enterprise Edition Changes

Issue ID	Category	Description
GG-51427	Cluster Data Snapshots and Recovery	Fixed snapshot creation stopping when a race occurs during cache group destruction.
GG-51315	Cluster Data Replication	Fixed an issue that could cause data replication to get stuck.
GG-51196	Cluster Data Snapshots and Recovery	Tightened security of the point-in-time recovery partition-transfer handler.
GG-51177	Cluster Data Snapshots and Recovery	Tightened security of snapshot metadata deserialization.

Issue ID

Control Center Agent Changes

Issue ID	Category	Description
GG-51138	Control Center Agent	OIDC-based authentication can now retrieve a user’s role from an access token.
GG-51019	Control Center Agent	Fixed thread leaks in the Control Center agent’s WebSocket transport on connection failures and coordinator handover.

Issue ID

Installation and Upgrade Information

See the Rolling Upgrades page for information about how to perform automated upgrades and for details about version compatibility.

Migrating from GridGain 8.9.17 or Earlier With Java 8

Starting GridGain 8.9.18, GridGain uses Lucene 9 by default. As Lucene 9 requires Java 11, it will be impossible to run GridGain on Java 8 with default configuration.

To continue using Java 8 when migrating to GridGain 8.9.18 or later, replace the {GRIDGAIN_HOME}/libs/ignite-lucene-9 folder with {GRIDGAIN_HOME}/libs/optional/ignite-lucene-8.

Migrating From GridGain 8.9.0

GridGain 8.9.1 introduced a large number of changes in default configuration values. Your setup may be affected if you are using default configuration.

When migrating to GridGain 8.9.38, make sure to check Changed Default Values in GridGain 8.9.1 and Later section for any parameters you need to change.

Migrating From GridGain 8.X

When migrating from GridGain 8.8 to GridGain 8.9, no special actions are required for core functionality migration. By using rolling upgrades, you can update from any GridGain version listed below. You may need to perform minor configuration changes to ensure stability post migration.

If you are using GridGain Enterprise or Ultimate, the COPY command was reworked as described in the [COPY Command Changes] section. The syntax for working with CSV remains the same, but the path is now calculated on the node and the client. This change does not affect GridGain Community edition.

To disable this behavior and use the old copy command, pass the disabledFeatures=SERVER_BULK_LOAD parameter in the JDBC connection command:
```
jdbc:ignite:thin://127.0.0.1/?disabledFeatures=SERVER_BULK_LOAD
```
If you are using one of the optional modules listed in the [Removed Modules] section, they will continue to work, but compatibility and stability on GridGain 8.9 is not guaranteed. Consider using the alternatives:
- Visor CMD and GUI can be replaced by GridGain Control Center.
- The spark module can be replaced by the Spark Ignite Extension.
If you are using default values in your configuration, you may need to set them manually to keep you cluster working the same way as in previous versions. Make sure to check Changed Default Values in GridGain 8.9.1 and Later section for any parameters you need to change.

Older GridGain Versions Compatibility

Below is a list of versions that are compatible with the current version. You can rolling-upgrade from any of those. Compatibility with other versions is not guaranteed. If you are on a version that is not listed, contact GridGain for information on upgrade options.

8.9.16, 8.9.16-p1, 8.9.16-p2, 8.9.16-p3, 8.9.17, 8.9.17-p1, 8.9.18, 8.9.19, 8.9.20, 8.9.20-p1, 8.9.21, 8.9.22, 8.9.22-p1, 8.9.22-p2, 8.9.23, 8.9.24, 8.9.25, 8.9.26, 8.9.27, 8.9.28, 8.9.29, 8.9.30, 8.9.31, 8.9.32, 8.9.33, 8.9.34, 8.9.35, 8.9.36, 8.9.37

Older Thin Clients Compatibility

In most cases, older versions of thin clients should be compatible with newer versions of GridGain. Below is the list of versions of thin clients that are tested for compatibility with the latest version. The compatibility also means that you can safely update from any version on the list to any subsequent version.

Apache Ignite Versions Compatibility

Below is a list of versions that are tested for basic compatibility with the current version. If you are on a version that is not listed, contact GridGain for information on upgrade options.

2.11.1, 2.12.0, 2.13.0, 2.14.0, 2.15.0, 2.16.0, 2.17.0, 2.18.0

Apache Ignite thin clients are not compatible with GridGain. When switching to GridGain, follow the migration instructions to switch to GridGain clients.

Known Limitations

LEFT OUTER JOIN Behavior Change in GridGain 8.9.31

GridGain 8.9.31 fixes an issue in which the WHERE conditions could be incorrectly pushed down into the right branch of LEFT OUTER JOIN operations during query optimization. This optimization could cause queries to return incorrect results by effectively converting LEFT OUTER JOIN operations into INNER JOIN.

Starting with GridGain 8.9.31, the query optimizer correctly prevents WHERE conditions from being pushed down into the right branch of LEFT OUTER JOIN, ensuring that queries return the correct results according to SQL standards.

If your environment expects incorrect results, you set the new DIGNITE_FORCE_PUSHDOWN_CONDITIONS_TO_LEFT_JOIN system property to true on each node in your cluster. Review all affected queries and update them as needed before removing this property.

Java 8 Support in GridGain 8.9.18 and Later

Starting GridGain 8.9.18, GridGain uses Lucene 9 by default. As Lucene 9 requires Java 11, it will be impossible to run GridGain on Java 8 with default configuration.

We recommend switching to Java 11 or later before updating to GridGain 8.9.18 or later.

To continue using Java 8, replace the {GRIDGAIN_HOME}/libs/ignite-lucene-9 folder with {GRIDGAIN_HOME}/libs/optional/ignite-lucene-8.

Unsupported Features When Using Java 8 in GridGain 8.9.17

In GridGain 8.9.17, full text search is not supported when GridGain is running on Java 8. The new vector search feature requires using Java 11.

Additionally, GridGain 8.9.16 or earlier automatically created full text indexes for caches with string values, which may cause issues for working with the cache while using Java 8. To avoid this behavior, set the sql.disableCreateLuceneIndexForStringValueType property to true. If such index is already built for a cache with persistence, contact our support team for assistance with removing it.

We recommend switching to Java 11 or later before updating to GridGain 8.9.17 if you plan to use these features.

Changed Permissions for Control Center Agent in GridGain 8.9.4 and Later

GridGain 8.9.4 introduced stricter permissions checking for Control Center Agent. When running secured clusters, some actions that previously were available without permissions, will now require additional permissions.

Before updating, make sure to provide the required permissions, otherwise some actions may become unavailable.

New TRACING_CONFIGURATION_UPDATE Permission in GridGain 8.9.2 and Later

GridGain 8.9.2 introduced the TRACING_CONFIGURATION_UPDATE permission. If you were using security on a cluster before updating to this version, make sure that you provide the permissions to control utilities or users who need to update cluster permissions. Otherwise, they will not be able to update

Changed Default Values in GridGain 8.9.1 and Later

If you are updating from GridGain 8.8.X or 8.9.0, a large number of default values have been changed.

These changes may affect the stability or performance of your cluster if you are using default values.

We recommend checking the list below to make sure the changes do not have an adverse effect, and setting the value manually if necessary.

Service processor now use event-driven implementation by default. You can keep the old behavior by setting the IGNITE_EVENT_DRIVEN_SERVICE_PROCESSOR_ENABLE property to false. Make sure that all nodes in the cluster are set to the same value. See Services documentation for more information.
Data region metrics are now enabled by default. This may have a minor (within 2%) adverse effect on performance. You can keep the old behavior by setting the DataRegionConfiguration.metricsEnabled value to false.
Data storage metrics are now enabled by default. This may have a minor (within 2%) adverse effect on performance. You can keep the old behavior by setting the DataStorageConfiguration.metricsEnabled value to false.
TcpCommunicationSpi communication protocol now has a limit of 4096 messages for the outgoing messages queue by default.
Atomic operations are now not allowed in transactions by default. You can keep the old behavior by setting the IGNITE_ALLOW_ATOMIC_OPS_IN_TX value to true.
Logs are now in verbose mode by default. You can use the -q command line argument in the ignite.sh script to keep current log behavior.
SQL queries are now loaded lazily by default. This reduces memory consumption on medium and large queries and potentially improves garbage collection performance. You can keep the old behavior by setting the SqlFieldsQuery.setLazy(false).
Cache entries are now read from primary partitions by default, even if an entry is available on the node in a backup partition. This may have a minor performance impact, but significantly increases cluster stability. You can keep the old behavior by setting the readFromBackup property to true.
Partition map exchange transactions now time out after 1 minute instead of 0 (infinite) by default. You can keep the old timeout by setting the TX_TIMEOUT_ON_PARTITION_MAP_EXCHANGE setting to 0.
Data streamer now overwrites entries by default. You can keep the old behavior by setting the stmr.allowOverwrite property to false.
TCP discovery now uses static IP finder TcpDiscoveryVmIpFinder by default. To keep the old behavior, set the IP finder to use multicast IP finder.
Checkpointing process now starts upon reaching 75% of minWalArchiveSize instead of 25%. You can keep the old behavior by setting the IGNITE_CHECKPOINT_TRIGGER_ARCHIVE_SIZE_PERCENTAGE system variable to 0.25.

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Last updated on Sep 25, 2026