What’s New in This Release

Introduction

This release includes many improvements and introduces several new features covered below.

New Features

  • To boost the performance of join queries, GridGain now supports the hash join algorithm. Hash joins can be more efficient than nested loop joins in several scenarios, except for situations when the probe side of the join is very small. However, hash joins can only be used with equi-joins - a type of join with equality comparison in the join predicate. For more details and usage examples, refer to the Hash Joins documentation.

  • C++ users can now create objects with fields of Enum type and store them in their GridGain cluster.

  • We released an experimental version of the partition awareness feature that boosts the performance of the thin clients for .NET, C++, Python, and Node.js. The thin clients become aware of the distribution of partitions in the cluster, which allows sending requests directly to the nodes that keep primary copies of requested data. Partition awareness is also available for the JDBC Thin driver, which can help optimize the performance of SQL queries.

Improvements for Data Center Replication

Changes In Behavior

  • The default implementation of the sender storage has changed from an in-memory store to a disk-based store. All updates in the master cluster are now stored on disk on the sender nodes before they are forwarded to the remote cluster. The directory on the file system where data updates are stored can be configured using the DrSenderFsStore.directoryPath property. The default value points to a directory inside the node’s working directory. However, we recommend that you configure the directory explicitly.

    <bean class="org.gridgain.grid.configuration.DrSenderConfiguration">
    <!-- this node is part of group1 -->
    <property name="senderGroups">
        <list>
            <value>group1</value>
        </list>
    </property>
    <!-- connection configuration -->
    <property name="connectionConfiguration">
        <bean class="org.gridgain.grid.dr.DrSenderConnectionConfiguration">
            <!-- DR storage -->
            <property name="store">
                <bean class="org.gridgain.grid.dr.store.fs.DrSenderFsStore">
                    <property name="directoryPath" value="/path/to/store"/>
                </bean>
            </property>
            <!-- The ID of the remote cluster -->
            <property name="dataCenterId" value="2"/>
            <!-- Addresses of the remote cluster's receiver nodes -->
            <property name="receiverAddresses">
                <list>
                    <value>172.25.4.200:50001</value>
                </list>
            </property>
        </bean>
    </property>
</bean>

  • When the sender store gets full or corrupted, the replication process will stop. You will have to start it manually and do a full state transfer after addressing the problem that caused the issue.

  • The GridDr.pause()/GridDr.resume() methods are deprecated and replaced with GridDr.stopReplication()/GridDr.startReplication().

    The stopReplication() method terminates the replication process, i. e. cache updates will stop being processed.

    The startReplication() method resumes the replication process, i. e. cache updates will start being processed again. Note that if during the break the data in the cache has changed, you will need to do a full state transfer.

  • Added capability to pause/resume the replication process on the sender nodes. These operations can be performed via the JMX beans.

    Caution
    		 Do not confuse the pause/resume operations with the GridDr.pause()/GridDr.resume() methods, which have been deprecated.

    Unlike the GridDr.stopReplication() method, the pause operation will not terminate the process; instead, the sender node where the method is called will stop sending the updates to the remote cluster. The updates will continue to be processed and will be accumulated in the sender storage on that node. To resume the process of sending the updates to the remote cluster, perform the resume operation on the sender node.

    Important
    		 If you want to pause replication, you will have to pause and resume it on every sender node.

  • Added adaptive throttling feature that, depending on the workload, allows for adjusting the data transfer rate between data nodes and sender nodes, and between sender nodes and receiver nodes

  • Added several data replication event types. For the complete list of events, refer to the DR Events section.

  • Added the ability to enable replication for existing caches.

Removed/Deprecated

The GridDr.pause() and GridDr.resume() methods in the GridDr interface have been deprecated. Use GridDr.stopReplication()/GridDr.startReplication() methods instead.

Installation and Upgrade Information

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

Upgrade from versions 8.4.4 and 8.4.5

There is a known compatibility issue found in version 8.7.8.

To upgrade from versions 8.4.4 or 8.4.5 to version 8.7.8, perform the following steps:

  1. Stop one node and set the IGNITE_PDS_WAL_REBALANCE_THRESHOLD environment variable to 2147483647; then start the node. Repeat this procedure for all nodes in the cluster.

  2. Then perform a regular rolling upgrade procedure.

Known Issues

GG-25532

There is a known vulnerability in the 'spark-ml-model-parser' module caused by the dependent library zookeeper v. 3.4.13. If you do not use this module, your cluster is not affected by this vulnerability.

GG-25828

JDBC Driver version 8.7.7 cannot connect to cluster version 8.7.8 when authentication is enabled in the cluster.

GG-25723

An attempt to change the baseline topology under load may raise a 'VisorIllegalStateException' exception.

Fixed Issues

GridGain Community Edition Changes

IGN-12835

Cache

Improved speed of persistent node restart in case the node stopped during checkpoint.

IGN-11122

Cache

All critical errors during tx commit failures are now handled by a failure handler.

IGN-11457

Cache

Logical recovery phase is performed before a node joins the topology.

GG-19543

Communication

Changed client reconnection logic to speed up the reconnect process in case of failures.

GG-18799

Communication, Thin clients

Thin client: removed limitation of the length of credentials during handshake.

GG-18670

Diagnostics

Added diagnostic tool of dumping WAL page history in case of B+Tree getting corrupted.

GG-18667

Diagnostics

Added diagnostic ability for dumping page locks state like a thread dump.

GG-17442

Diagnostics

List of files in the classpath is printed during the start of the node. It can be disabled by setting ignite system property IGNITE_LOG_CLASSPATH_CONTENT_ON_STARTUP to false. By default, it is enabled.

GG-14947

Discovery

Client node cut off by communication from the rest of the cluster is stopped by Communication Failure Resolver.

IGN-7398

JDBC Thin Driver

Added Statement.cancel() support.

IGN-7397

JDBC Thin Driver

Added Statement.setQueryTimeout() support.

IGN-7193

JDBC Thin Driver

Implemented Connection.setNetworkTimeout method.

GG-23437

Rebalancing

Fixed the issue of resource utilization during rebalancing.

GG-18917

Rebalancing

Rebalance properties were moved from CacheConfiguration to IgniteConfiguration level. Rebalance properties in CacheConfiguration were deprecated.

IGN-3517

Storage Engine

Cache configurations are not explicitly deserialized on non-affinity nodes.

IGN-13624

Storage Engine

Optimized amount of heap space used for affinity assignment history storing.

IGN-13478

SQL

SqlQuery is deprecated. SqlFieldsQuery should be used instead.

GG-19125

SQL

Added support for the row count statistics which helps with the local queries optimization.

GG-18538

SQL

Supports hash index is built on the fly that is used for join when hash table can be placed in the memory.

IGN-12376

SQL

Support partition pruning for SQL statements with joins.

IGN-8004

SQL

Restricted DML execution when there is an active transaction over TRANSACTIONAL caches; can be overridden by using the IGNITE_ALLOW_DML_INSIDE_TRANSACTION system property.

GG-21272

Transactions

Added ability to track system and user time for transactions.

GridGain Enterprise Edition Changes

GG-23261

Data Center Replication

Default DrStore mode is changed to STOP.

GG-21367

Data Center Replication

Added correctly named methods for DR start\stop methods.

GG-22491

Data Center Replication

Added adaptive DR throttling.

GG-22626

Data Center Replication

Added metrics to show DR sender/receiver pending queues size.

GG-21930

Data Center Replication

Sender hub configuration uses a single port for localOutboundAddress.

GG-21368

Data Center Replication

Fixed broken DR pause\resume semantic.

GG-12739

Data Center Replication

Fixed data center replication for caches created via DDL.

GG-22661

Data Center Replication

A file-system based implementation of Sender Store is now used by default. It has a default work directory, but we recommend to configure it explicitly for production environments.

GridGain Ultimate Edition Changes

GG-13635

Snapshots

Added the ability to disable automatic snapshot creation after baseline changes. The behavior can be configured via GG_DISABLE_SNAPSHOT_ON_BASELINE_CHANGE_WITH_ENABLED_PITR parameter.

GG-13330

Snapshots

Added -check option to CATALOG command.

GG-14095

Snapshots

Fixed the issue when MOVE and COPY snapshot operation could be interrupted in the middle of the process if a large file was copied.

Related Information

Need more details? Please don’t hesitate to reach out to the GridGain Customer Support team.

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