GridGain Developers Hub

GridGain 8.8.6 Release Notes

New Features

.NET Thin Client Supports Data Streaming

Data streaming was added to .NET thin client. You can now use it in your thin clients in the same way you use it in normal client.

.NET Streaming API Extended

Data streaming API for .NET client was extended:

  • AddData and RemoveData methods were deprecated.

  • void Add and void Remove methods were added and should be used instead.

  • The new BatchTask property was added. You can use it to get the task for the current batch.

using System;
using System.Threading.Tasks;
using Apache.Ignite.Core;
namespace IgniteNewDataStreamerApi
    class Program
        static async Task Main(string[] args)
            using var ignite = Ignition.Start();
            var cache = ignite.CreateCache<int, string>("my-cache");
            using var streamer = ignite.GetDataStreamer<int, string>(cache.Name);
            streamer.AllowOverwrite = true;
            streamer.Add(1, "Hello");
            streamer.Add(2, "World");
            await streamer.FlushAsync();

Gzip Data Compression Now Supports Snapshots

With this release you can use gzip data compression to create caches for nodes with snapshots. You can also disable dictionaries for ZSTD compression with dictionaryRequired=false dictionarySize=0 to work with snapshots, but using gzip is recommended.

Due to improvements in GridGain 8.8.6 it is no longer recommended to use -XX:+DisableExplicitGC JVM option. Using this option no longer provides any benefits and can cause the heap to no longer be reclaimed.

Improvements and Fixed Issues

Community Edition Changes

Issue ID Category Description


Platforms & Thin Clients

.NET: Added thin client DataStreamer API.


Platforms & Thin Clients

Thin clients: enable partition awareness by default (Java, .NET, C++).


Cluster Storage Engine

Fixed an issue when multiple checkpoints in a single WAL segment could lead to incorrect WAL reservation.


Cluster SQL Engine

SqlOffloadingEnabled setting is now correctly logged.


Cluster SQL Engine

Improved performance of SQL queries that use DISTINCT expression.


Platforms & Thin Clients

ODBC now works with GUID data type on Windows.


Cluster SQL Engine

Added parameters to ANALYZE command to manually override statistics. Added manually overridden values to statistics_configuration system view.


Platforms & Thin Clients

.NET: Improved DataStreamer API - added FlushAsync, deprecated and replaced confusing methods and properties, fixed resource cleanup.


Cluster Discovery

Improved local node discovery and default configuration on z/OS.


Distributed Data Structures

Added more messages to DEBUG logs of data structures.


Cluster Storage Engine

Fixed AssertionError that could happen on the first checkpoint after a node start.


GridGain Integrations

Error during Cassandra Cache Store initialization was fixed.


Cluster SQL Engine

Fixed an issue when a node restart during index rebuild caused errors or index corruption.

Enterprise Edition Changes

Issue ID Category Description


Cluster Data Replication

Fixed an issue when incremental state transfer future could never be completed.


Cluster Data Replication

Fixed AssertionError during cluster rolling restart when DR is enabled.


Cluster Rolling Upgrade

Fixed "Authorization failed" error when the rolling upgrade was started on a cluster with security enabled.


Cluster Data Replication

Fixed memory consumption when Data center replication is enabled and a network issue between the data centers occurs.


Cluster Storage Engine

Fixed data corruption in GG Ultimate Edition when TDE-enabled caches are used.


Cluster Storage Engine

It is now possible to use snapshots together with data compression that uses Gzip or Zstandard without dictionary.


Cluster Metrics & Monitoring

Added new metrics for monitoring the number of memory pages related to SQL indexes. These metrics can be made available through JMX and viewed as part of data region and cache group properties under the InMemoryIndexPages name.


Control Center Agent

Running SQL queries from Control Center no longer requires superfluous ADMIN_OPS permission.


Binary Objects

Added gzip-based data compression feature.

Ultimate Edition Changes

Issue ID Category Description


Cluster Data Snapshots and Recovery

Optimized snapshots restoration from shared network folders.


Cluster Snapshot Utility commands (move, check, delete) now log on INFO level instead of WARN.

Installation and Upgrade Information

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

8.7.2-p15, 8.7.3, 8.7.33-p2, 8.7.4, 8.7.5, 8.7.6, 8.7.7, 8.7.8, 8.7.9, 8.7.10, 8.7.11, 8.7.12, 8.7.13, 8.7.14, 8.7.15, 8.7.16, 8.7.17, 8.7.18, 8.7.19, 8.7.19-p1, 8.7.20, 8.7.21, 8.7.22, 8.7.23, 8.7.24, 8.7.25, 8.7.26, 8.7.26-p1, 8.7.27, 8.7.27-p1, 8.7.28, 8.7.29, 8.7.29-p1, 8.7.30, 8.7.31, 8.7.32, 8.7.33, 8.7.34, 8.7.35, 8.7.36, 8.7.5-p1, 8.7.6-p1, 8.8.1, 8.8.2, 8.8.3, 8.8.4, 8.8.5

Known Limitations

Jetty Configuration Incompatibility in GridGain 8.7.21 and Later

If you are upgrading from version 8.7.20 or earlier, consider an incompatibility issue related to Jetty configuration introduced in GridGain 8.7.21.

Your setup may be affected if:

  • You use the ignite-rest-http module (e.g. to connect to GridGain Web Console)

  • You have a custom Jetty configuration that enables SSL for REST

  • Your Jetty configuration uses the org.eclipse.jetty.util.ssl.SslContextFactory class

  • The keystore specified in the Jetty configuration contains both the CA certificate and the private certificate

In this case, after starting a new version, an exception is thrown with an error message similar to the following:

java.lang.IllegalStateException: KeyStores with multiple certificates are not supported on the base class
org.eclipse.jetty.util.ssl.SslContextFactory. (Use org.eclipse.jetty.util.ssl.SslContextFactory$Server
or org.eclipse.jetty.util.ssl.SslContextFactory$Client instead)

To workaround this issue, alter the Jetty configuration to use org.eclipse.jetty.util.ssl.SslContextFactory$Server or org.eclipse.jetty.util.ssl.SslContextFactory$Client. See the configuration example at the Client Certificate Authentication page.

Default rebalanceThreadPoolSize in GridGain 8.7.26 and Later

In GridGain 8.7.26, the default value of the property IgniteConfiguration.rebalanceThreadPoolSize changed from 1 to min(4, number of CPU / 4). It may cause a compatibility issue under the following conditions:

  • When a Rolling Upgrade is performed

  • The upgrade is performed from 8.5.7 version (or earlier) to 8.5.x or from 8.7.3 (or earlier) to 8.7.x

  • The server nodes have at least 8 CPU cores

  • The nodes configuration does not have the property IgniteConfiguration.rebalanceThreadPoolSize, so the default value is used

In this case, an exception is thrown with an error message similar to the following:

сlass org.apache.ignite.IgniteException: Rebalance configuration mismatch (fix configuration or set -DIGNITE_SKIP_CONFIGURATION_CONSISTENCY_CHECK=true system property).
Different values of such parameter may lead to rebalance process instability and hanging.  [rmtNodeId=5fc58fb7-209d-489a-8034-0127a81abed6, locRebalanceThreadPoolSize = 4, rmtRebalanceThreadPoolSize = 1]

To workaround this issue, change the configuration of the server nodes to rebalanceThreadPoolSize=1 so that it matches the previous default configuration. For example:

<bean class="org.apache.ignite.configuration.IgniteConfiguration">
    <property name="rebalanceThreadPoolSize" value="1"/>

    <!-- The rest of the configuration goes here -->

Jetty Doesn’t Accept Incorrect Configuration in GridGain 8.7.31 and Later

In GridGain 8.7.31 Jetty was upgraded to 9.4.33. Starting that version, Jetty has more strict validation of the provided configuration files. Before that version, an incorrectly spelled property in the configuration file had no effect. Starting this version, errors in the configuration will lead to an error on start.

Your setup may be affected if:

  • You use the ignite-rest-http module (e.g. to connect to GridGain Web Console)

  • You have a custom Jetty configuration for REST

  • The custom configuration has errors in it

You will need to fix the custom Jetty configuration before upgrading. No Longer Enables Remote JMX by Default in GridGain 8.7.31 and Later

Starting from 8.7.31 version, GridGain no longer attempts to automatically enable the remote JMX. Default settings are known to cause issues if customized (for example, secure the connection). Also, in most cases, remote JMX is not required since many tools use local JMX connections (not using TCP).

Your setup may be affected if:

  • You start GridGain nodes via script

  • You connect to GridGain nodes' JMX interface remotely over TCP using the default configuration

To continue using remote JMX, you need to manually specify the required JMX settings. Please see the example below. Note that you don’t need remote JMX if you use a local connection, such as connecting JConsole to a GridGain process on the same host.

export JVM_OPTS=" \"


Rolling Upgrade from GridGain 8.7.9 and Earlier Fails if Data Center Replication is Enabled

Rolling upgrades from GridGain 8.7.9 and earlier to current GridGain version fails if data center replication is enabled and under load.

To work around this issue, you can first upgrade to GridGain 8.7.21, or a later 8.7.x version, and then to current version.

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