Volt Active Data
11.4.16
VoltDB Operator 1.8.13 |
VoltDB Helm Chart 1.8.13 |
August 13, 2024
This document provides information about known issues and limitations to the current release of VoltDB. If you encounter any problems not listed below, please be sure to report them to support@voltactivedata.com. Thank you.
The process for upgrading from the recent versions of VoltDB is as follows:
Shutdown the database, creating a final snapshot (using voltadmin shutdown --save).
Upgrade the VoltDB software.
Restart the database (using voltdb start).
For Kubernetes, see the section on "Upgrading the VoltDB Software and Helm Charts" in the VoltDB Kubernetes Administrator's Guide. For DR clusters, see the section on "Upgrading VoltDB Software" in the VoltDB Administrator's Guide for special considerations related to DR upgrades. If you are upgrading from versions before V6.8, see the section on "Upgrading Older Versions of VoltDB Manually" in the same manual.
Finally, for all customers upgrading from earlier versions of VoltDB, please be sure to read the upgrade notes for your current and subsequent releases, including V6, V7, V8, and V10.
Users of previous versions of VoltDB should take note of the following changes that might impact their existing applications. See the VoltDB Operator Release Notes for changes specific to the use of VoltDB on the Kubernetes platform.
1. Release V11.4.16 (August 13, 2024) | ||||||||||||||
1.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated or removed to eliminate known security vulnerabilities, including:
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1.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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2. Release V11.4.15 (March 19, 2024) | ||||||||||||||
2.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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2.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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3. Release V11.4.14 (February 20, 2024) | ||||||||||||||
3.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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3.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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4. Release V11.4.13 (January 4, 2024) | ||||||||||||||
4.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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4.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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5. Release V11.4.12 (October 23, 2023) | ||||||||||||||
5.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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5.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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6. Release V11.4.11 (September 15, 2023) | ||||||||||||||
6.1. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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7. Release V11.4.10 (July 28, 2023) | ||||||||||||||
7.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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7.2. | Additional improvement | |||||||||||||
The following limitation. in previous versions has been resolved:
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8. Release V11.4.9 (July 15, 2023) | ||||||||||||||
8.1. | Support for Kubernetes version 1.25. | |||||||||||||
This release of the VoltDB Operator and Helm chart adds support for Kubernetes version 1.25. It can be used only on Kubernetes version 1.21 and later. Kubernetes removed support for the deprecated PodSecurityPolicy in version 1.25. To this end, the default
chart setting for | ||||||||||||||
8.2. | Kubernetes upgrade | |||||||||||||
The VoltDB base image on Kubernetes has been upgraded to use Java 17. | ||||||||||||||
8.3. | Additional improvements | |||||||||||||
The following limitation in previous versions has been resolved:
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9. Release V11.4.8 (June 27, 2023) | ||||||||||||||
9.1. | Kubernetes upgrade | |||||||||||||
The VoltDB base image on Kubernetes has been upgraded to use Alpine 3.18. | ||||||||||||||
9.2. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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9.3. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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10. Release V11.4.7 (May 23, 2023) | ||||||||||||||
10.1. | Improved memory management | |||||||||||||
This release provides additional information and control when managing memory on VoltDB servers and in particular, the undo pool. The undo pool is used to store temporary information needed to "undo" a transaction in case it must be rolled back. The pool grows as needed, based on how much data is needed to undo the current transactions. If your workload includes certain infrequent but memory-intensive transactions (such as deleting large volumes of data on a weekly basis) the undo pool can grow quite large, artificially inflating the resident set size (RSS). A column has been added to the results of the @Statistics system procedure MEMORY selector. The column, UNDO_POOL_SIZE, measures the amount of memory, in kilobytes, allocated for the undo pool. A new system procedure, @PurgeUndo, lets you reset the undo pool size to zero. If you find your RSS growing incrementally and you suspect the undo pool, you can use the UNDO_POOL_SIZE column in the @Statistics MEMORY procedure results to verify the amount of space being consumed by the undo pool. If the pool is unnecessarily large, you can use the @PurgeUndo procedure to reset it. | ||||||||||||||
11. Release V11.4.6 (May 15, 2023) | ||||||||||||||
11.1. | Using VoltDB where the /tmp directory is noexec | |||||||||||||
On startup, VoltDB extracts certain native libraries into the /tmp directory before loading them. This works in all standard operating environments. However, in custom installations where the /tmp storage is mounted with the "noexec" option, VoltDB cannot extract the libraries and, in the past, refused to start. For those cases where the /tmp directory is assigned on storage mounted with the ‘noexec’ option, you can assign an alternative storage for VoltDB to use for extracting and executing temporary files. This is now done automatically on Kubernetes and does not require any user intervention. On non-Kubernetes environments, you can identify an alternative location by assigning it to
export VOLTDB_OPTS="-Dvolt.tmpdir=/volttemp \ -Dorg.xerial.snappy.tempdir=/volttemp \ -Djna.tmpdir=/volttemp" When using an alternate temporary directory, files can accumulate over time since the directory is not automatically purged on startup. So you should make sure you periodically delete old files from the directory. | ||||||||||||||
11.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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12. Release V11.4.5 (March 23, 2023) | ||||||||||||||
12.1. | Support for JDBC getMaxConnection method | |||||||||||||
The Volt JDBC API now supports the getMaxConnection method, which returns the integer value of zero (0) indicating the maximum is unspecified. | ||||||||||||||
12.2. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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12.3. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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13. Release V11.4.4 (February 16, 2023) | ||||||||||||||
13.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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13.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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14. Release V11.4.3 (November 3, 2022) | ||||||||||||||
14.1. | Security updates | |||||||||||||
Various packages within Volt Active Data have been updated to eliminate known security vulnerabilities, including:
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14.2. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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15. Release V11.4.2 (September 8, 2022) | ||||||||||||||
15.1. | Help for the Prometheus agent | |||||||||||||
The Volt Prometheus agent provides metrics concerning the database performance and status in a format
appropriate for the Prometheus monitoring system through the URL | ||||||||||||||
15.2. | Additional improvement | |||||||||||||
The following limitation in previous versions has been resolved:
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16. Release V11.4.1 (August 11, 2022) | ||||||||||||||
16.1. | General release of the Helm voltadmin plugin | |||||||||||||
The Helm plugin voltadmin is now ready for production use. The plugin simplifies the management of VoltDB clusters in Kubernetes by replicating commands, such as dr reset, pause, resume, and shutdown, found in voltadmin on non-Kubernetes systems. The Helm plugin is a separate installation from the standard VoltDB Helm charts. It requires the same versions of Python, Helm, and Kubernetes as the Volt software; plus an additional Python module, click (version 8.0.1 or later). To install the plugin:
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16.2. | Production support for Java 17 | |||||||||||||
Java 17 is now fully tested and supported for production use with Volt Active Data. | ||||||||||||||
16.3. | Additional statistics for tracking communication between XDCR clusters | |||||||||||||
Several additional columns have been added to the first results table for the @Statistics DRPRODUCER selector (and the corresponding Prometheus agent metrics) to help evaluate the time between when binary logs are ready for transmission and when acknowledgement is received from the consumer. The new columns are the following and are reported in milliseconds:
The corresponding metrics in the Prometheus agent are:
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16.4. | Sample dashboards for Grafana | |||||||||||||
Grafana is a popular solution for graphing and displaying information collected by Prometheus. A major benefit of using Prometheus and Grafana together is that you can integrate metrics from multiple applications to create a custom dashboard for your business. To get you started, Volt provides a set of dashboards offering different views of the database cluster's performance, status, and features. The dashboards are available in Grafana JSON format from a public Github repository: https://github.com/VoltDB/volt-monitoring/ You can copy and install the individual dashboards manually, include them via the Grafana REST API, or use any of the other methods for installing dashboards. See the Grafana documentation and the README file for the Volt dashboards for more information. | ||||||||||||||
16.5. | Security update | |||||||||||||
The reload4j library has been updated to eliminate a known security vulnerability (CVE). | ||||||||||||||
16.6. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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17. Release V11.4 (June 27, 2022) | ||||||||||||||
17.1. | Compound procedures | |||||||||||||
Volt V11.4 introduces a new type of procedure: the compound procedure. Compound procedures let you call multiple transactional procedures, process results, define error handling and include other business processing within a single procedure that can be invoked with a single call. This is particularly useful as a target for topics, where each record invokes a single procedure. Compound procedures expand the capabilities of topic processing providing almost limitless flexibility. At the same time, it is important to recognize that compound procedures are not transactional. Although each regular stored procedure invoked by the compound procedure will complete or rollback as a unit, the compound procedure itself does not and must provide its own error handling and recovery. For more information, see the chapter on Using Compound Procedures in the VoltDB Performance and Customization Guide. | ||||||||||||||
17.2. | Topics now support tables as well as streams | |||||||||||||
This release extends Volt topics to include support for input from tables, integrating with many existing table features — including migration, time to live (TTL) and change data capture. Specifically, the latest version includes the following features:
These features are described in more detail in the CREATE TABLE reference pages in the Using VoltDB guide. | ||||||||||||||
17.3. | Stream views now support time-to-live (TTL) and migration | |||||||||||||
Stream views, which are computed based on ephemeral data passing through streams rather than persistent data in tables, can be managed by manually updating and deleting records from the view. You can now automate the management process with the USING TTL clause for scheduling the deletion of records based on a column in the view. You can also use the MIGRATE TO TARGET and MIGRATE TO TOPIC clauses for archiving view records before they are deleted. See the description of the CREATE VIEW statement in the Using VoltDB guide for more details. | ||||||||||||||
17.4. | New ALTER VIEW statement | |||||||||||||
Now that you can automate the management of stream views with the USING TTL clause, an ALTER VIEW ALTER USING TTL... statement has been added so you can modify certain aspects of the view without deleting it. The ALTER VIEW statement lets you modify the TTL value, the batch size, and the frequency of TTL processing. See the description of ALTER VIEW in the Using VoltDB guide for details. | ||||||||||||||
17.5. | Additional statistics | |||||||||||||
Several different categories of statistics have been added to the @Statistics and @SystemInformation system procedures. The new selectors for the @Statistics system procedure are the following:
The new data provided by the @SystemInformation includes the following:
See the descriptions of @Statistics and @SysteInformation in the Using VoltDB guide for more information. | ||||||||||||||
17.6. | Improved Prometheus support | |||||||||||||
The data available from the VoltDB Prometheus agent has been significantly extended and rationalized. Specifically:
Additional information about the Prometheus agent and what data is available through it will be provided in upcoming releases. | ||||||||||||||
17.7. | Support for Rocky Linux | |||||||||||||
Rocky Linux version 8.0 has been added as a supported base platform for VoltDB. Rocky Linux is a replacement for CentOS, which has reached end of life and is no longer supported by Red Hat, its sponsor. | ||||||||||||||
17.8. | Support for Kubernetes 1.23.0 | |||||||||||||
The VoltDB Operator and Helm charts now support Kubernetes 1.23.0. | ||||||||||||||
17.9. | Ability to choose which Java Garbage Collector to use | |||||||||||||
VoltDB provides a new environment variable that you can use to select which Java garbage collector the server process uses. By defining VOLTDB_GC_OPTS before starting the server, you can specify the Java arguments necessary for selecting a garbage collector and setting any related properties it needs. For example, the following selects the G1 garbage collector and sets string deduplication: $ export VOLTDB_GC_OPTS="-XX+useG1GC -XX+UseStringDeduplication" $ voltdb start --dir=~/mydb -H serverA Note that the garbage collector has a significant impact on memory-intensive applications like VoltDB. Also, VoltDB does not validate the correctness of the arguments you specify. So this option should be used with great caution. See the appendix on server configuration options in the VoltDB Administrator's Guide for more details. | ||||||||||||||
17.10. | New function TIME_WINDOW() | |||||||||||||
There is a new function, TIME_WINDOW(), that defines time slices (such as every 15 minutes) that you can use for windowing applications. TIME_WINDOW() can be particularly useful when used in conjunction with stream views. For example, the following example tracks the number of stock events (buys and sells) in five minute "windows" so activity can be assessed without having to keep all of the underlying transaction data. CREATE VIEW volatility (total, event_type, window) AS SELECT count(*), buy_or_sell, TIME_WINDOW(MINUTE, 5, trx_time) FROM transactions GROUP BY buy_or_sell, TIME_WINDOW(MINUTE, 5, trx_time); | ||||||||||||||
17.11. | New function DATEDIFF() | |||||||||||||
The new DATEDIFF() function provides the difference between two timestamps in the requested units. The result of the function is an integer value. For example, the following function returns the number of whole minutes between the login and logout timestamps: INSERT INTO billing (account_id, minutes) SELECT user, DATEDIFF(MINUTE,login, logout) FROM session; | ||||||||||||||
17.12. | Change to CREATE PROCEDURE statement for DIRECTED and COMPOUND procedures | |||||||||||||
With the addition of compound procedures, the syntax for the CREATE PROCEDURE statement has been modified. Previously, the syntax for creating a directed procedure was CREATE PROCEDURE DIRECTED. The syntax has been updated to be grammatically correct, putting the adjective first. The new statements are CREATE COMPOUND PROCEDURE and CREATE DIRECTED PROCEDURE. | ||||||||||||||
17.13. | @SwapTables no longer allowed on active XDCR clusters | |||||||||||||
The @SwapTables system procedure acts like a schema change, which on cross-datacenter replication (XDCR) clusters requires that the cluster be paused before changing the schema. However, previously the system procedure did not enforce this requirement. Now @SwapTables returns an error when the system procedure is invoked if the XDCR cluster is not paused. | ||||||||||||||
17.14. | Deprecating obsolete features | |||||||||||||
As Volt Active Data evolves, certain features are replaced or become obsolete. When this happens, they are deprecated, which means their use is no longer recommended and they are removed from the product in a future release. The following features are now deprecated.
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17.15. | Security update | |||||||||||||
VoltDB does not use any of the Log4J components implicated in the published CVEs. However, to avoid any confusion, VoltDB has replaced the Log4J library with reload4J, a drop-in replacement that replicates the log4J namespace and functionality, but eliminates all known security vulnerabilities. | ||||||||||||||
17.16. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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18. Release V11.3.2 (June 15, 2022) | ||||||||||||||
18.1. | Recent improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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19. Release V11.3.1 (April 21, 2022) | ||||||||||||||
19.1. | Welcome to Volt Active Data | |||||||||||||
VoltDB, the company, is now Volt Active Data. The in-memory database VoltDB continues to be the foundation of our product offering. This software release updates messages and other references to provide the most accurate and up-to-date access to product resources. | ||||||||||||||
19.2. | Volt Active Data monitoring in DataDog | |||||||||||||
Our partner, DataDog, offers monitoring services that let you combine metrics from multiple products into a single view of your business systems. Their support for Volt Active Data was recently improved and expanded. For more information, see their original blog post announcing Volt support or visit their website. | ||||||||||||||
19.3. | VoltDB Operator and Helm Charts updates | |||||||||||||
The VoltDB Operator and Helm charts for this release of Volt Active Data have been updated twice:
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19.4. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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20. Release V11.3 (February 8, 2022) | ||||||||||||||
20.1. | Beta Support for Java 17 | |||||||||||||
VoltDB is now beta testing the use of Java 17 for running VoltDB. This means you can use Java 8, 11, or 17 to run both the VoltDB server product and client API. Additional testing and validation is ongoing and Java 17 is expected to be ready for general release (and production use) in V11.4. | ||||||||||||||
20.2. | The new Java Client2 API is ready for production | |||||||||||||
A new Java client interface, Client2, was introduced as a beta feature in VoltDB V11.2. Testing is complete and this API is now generally available for production use. See the Client2 chapter in the VoltDB Performance and Customization Guide for an introduction to the interface and the Javadoc for details. | ||||||||||||||
20.3. | Prioritizing transactions | |||||||||||||
One feature of the new Client2 interface is the ability to specify a priority for individual procedure calls, which is now supported by the server as well. Priorities increase the frequency of high priority transactions running versus low priority transactions. You can specify a priority when calling a stored procedure, or you can specify a priority for classes of transactions, such as snapshot and database replication (DR) in the configuration file when you enable prioritization. See the chapter on Prioritizing Transactions in the VoltDB Performance and Customization Guide for information on enabling and specifying priorities. | ||||||||||||||
20.4. | Protection against mutable parameters in K-safe clusters | |||||||||||||
It is possible to pass mutable parameters most notably arrays to stored procedures. If you modify those parameters before passing them to a SQL statement, there is no guarantee that the results will be deterministic on all copies of the partition. Consequences can be unpredictable results, node crashes, or even data corruption. WarningTo avoid non-deteministic behavior, VoltDB now makes a copy of the mutable parameters before executing the statement. However, depending on the size of the arrays and the frequency of the calls, copying the parameters can consume large amounts of memory and could have a significant impact on performance. If you are sure you do not modify such arrays in your stored procedures, you can tell VoltDB to not copy mutable parameters in the configuration file. See the appendix on Server Configuration Options in the VoltDB Administrator's Guide for details. | ||||||||||||||
20.5. | Support for Kubernetes 22.0 | |||||||||||||
The VoltDB Operator and Helm charts now support Kubernetes V1.19.x through V22.x. | ||||||||||||||
20.6. | VoltDB Management Center improvements | |||||||||||||
A number of functional improvements have been made to the VoltDB Management Center (VMC), including:
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20.7. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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21. Release V11.2 (October 28, 2021) | ||||||||||||||
This release focuses on improving the management of resources associated with running VoltDB in production. In particular, several new features allow you to set a retention policy for logs, snapshots, and other files created by the database system. Several of these features have new default values to reduce the proliferation of unnecessary files, as well as options to adjust the policy to your business needs. | ||||||||||||||
21.1. | Retention policy for database log files | |||||||||||||
VoltDB writes informational, warning, and error messages to log files in a subfolder of the database root directory. By default, the log files "roll", creating a new file and renaming the old ones, on a daily basis. Previously, old log files were never deleted. Starting with this release, the default Log4J configuration file has been revised and now retains up to 30 log files. Older files are deleted. You can customize the configuration to change either or both the number of files retained or how frequently a new file is created. See the section on "Managing VoltDB Log Files" in the VoltDB Administrator's Guide for details. Note that if you use a customized Log4J configuration, your customization will take precedence and override the new behavior. | ||||||||||||||
21.2. | Retention policy for snapshots during initiation | |||||||||||||
By default, snapshots created manually or through periodic snapshots are stored in the
snapshots folder in the database root directory. When you reinitialize the root
directory, using the Snapshots can be quite large, since they save the entire contents of the database. And previously, VoltDB
saved and renamed all of the extant snapshot folders. To avoid consuming unnecessary disk space, the
voltadmin init --force command now only saves the two most recent snapshot folders by default.
You can specify a different retention value with the | ||||||||||||||
21.3. | Retention policy for final snapshots | |||||||||||||
When you shutdown the database with the voltadmin shutdown --save command, a final snapshot is created saving the database contents. Final snapshots are useful, particularly for saving and restoring the database when upgrading the VoltDB software. VoltDB does not delete the final snapshot after it is restored as a safety precaution, in case you decide the restored database has a problem or is not configured correctly. Saving the final snapshot gives you an opportunity to manually restore the database to another location in case of an emergency. However, once the final snapshot is restored and operational, the snapshot is no longer needed. Consequently, VoltDB now deletes all but the last two final snapshots when you create a new snapshot with the voltadmin shutdown --save command. This is a fixed limit. | ||||||||||||||
21.4. | Retention policy for XDCR conflict logs | |||||||||||||
Cross datacenter replication (XDCR) records any conflicts that occur during active-active replication in the XDCR conflict logs. These logs give you the opportunity to review, analyze, and potentially correct any issues that arise from conflicting transactions. However, over time, subsequent transactions will make correcting old conflicts impractical. How long you need to save the conflict logs is a business decision. Therefore, by default, VoltDB maintains
the old behavior of keeping all conflict logs. (Except in the case of Kubernetes, where a default of 30 days is
applied.) You can specify a retention policy in terms of how long to keep log files by adding the <dr id="1" role="xdcr" conflictretention="14d" > The retention period can be specified in seconds, minutes, hours, or days (using the signifier
s, m, h, or
d). Alternately, you can configure the VOLTDB_XDCR_CONFLICTS export connector, which
overrides the | ||||||||||||||
21.5. | Retention policy for file export | |||||||||||||
Similarly to XDCR conflict logs, a retention policy can be applied to the output files of any file export
connector. By default, all output files are retained. However, you can use the <export>
<configuration enabled="true" target="log" type="file">
<property name="retention">14d</property>
<property name="type">csv</property>
<property name="nonce">MyLogs</property>
</configuration>
</export> See the section on "The File Export Connector" in the Using VoltDB guide for details. | ||||||||||||||
21.6. | VoltDB now supports Kubernetes on OpenShift | |||||||||||||
The VoltDB Operator has added support for running VoltDB databases in Kubernetes on the OpenShift platform from Red Hat. This expands VoltDB's Kubernetes compatibility to three of the major cloud platforms: AWS, Google Cloud, and OpenShift. For those interested in using OpenShift, please be sure to read the operational note later in this document for specific instructions on handling Transparent Huge Pages (THP) on the OpenShift platform. | ||||||||||||||
21.7. | New Java client method for connecting to a list of potential hosts | |||||||||||||
The | ||||||||||||||
21.8. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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22. Release V11.1.1 (October 11, 2021) | ||||||||||||||
22.1. | Additional improvement | |||||||||||||
The following limitation in previous versions has been resolved:
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23. Release V11.1 (September 14, 2021) | ||||||||||||||
23.1. | New Java client API, Client2 (BETA) | |||||||||||||
VoltDB V11.1 includes the Beta release of a new Java client library. Client2 provides a modern, robust and extensible interface to VoltDB for client applications written in Java. For example, Client2 uses Completable Futures to return information from asynchronous procedure calls, providing a more structured way of handling both successful and unsuccessful calls. The new API will also be the main platform for new client development in the future, starting with the ability to assign a priority for individual requests. Client-side priority queuing is available in the beta release and allows the client to prioritize certain procedure calls over others. See the javadoc for details. As with all beta releases, the new capabilities are believed to work as described. However, further testing and customer feedback is required before we can recommend its use for production. We encourage you to try the new client interface and provide feedback to support@voltactivedata.com. Thank you. | ||||||||||||||
23.2. | New Helm plugin, voltadmin (BETA) | |||||||||||||
Helm and the VoltDB Operator make configuring and running VoltDB in Kubernetes easier. However, there are certain management operations that are awkward to perform using Helm properties alone. VoltDB provides a new Helm plugin, now in Beta release, to simplify these additional VoltDB management tasks. The Helm voltadmin plugin provides commands, similar to regular voltadmin commands, to perform management activities on a running cluster. For its initial release the Helm voltadmin plugin supports the following commands:
Additional commands will be added in future releases. Once installed, you use the plugin on the Helm command
line by specifying the plugin name (voltadmin), the name of the Helm release with the $ helm voltadmin --release=mydb dr reset --cluster=1 You can install the beta release of the voltadmin plugin with the following command: $ helm plugin install https://storage.googleapis.com/voltdb-kubernetes-charts/voltadmin-1.4.0-beta.tgz | ||||||||||||||
23.3. | New --credentials argument added to Prometheus agent | |||||||||||||
The Prometheus agent for VoltDB has a new argument available when starting the agent from the shell command.
The $ cat $HOME/mycreds.txt username: admin password: mySpecialPassword $ ./voltdb/tools/monitoring/prometheus/voltdb-prometheus \ --credentials $HOME/mycreds.txt Using the | ||||||||||||||
23.4. | Support for reporting incremental statistics in Prometheus | |||||||||||||
By default, the VoltDB Prometheus agent reports statistics for all time — since the database started.
You can now tell the agent to report statistics in increments, so that each timestamp reports on activity since the
last data was reported. For example, if data is collected every 10 seconds, the statistics for transactions per
second is the average TPS over the last 10 seconds, rather than the average since the server started. To report
incremental statistics, set the Helm property $ ./voltdb/tools/monitoring/prometheus/voltdb-prometheus --delta | ||||||||||||||
23.5. | Ability to set DSCP priority for DR network traffic | |||||||||||||
VoltDB now lets you set a DSCP priority level for network packets associated with database replication (DR) by defining the environment variable DD_SOCKET_TRAFFIC_CLASS to the DSCP value you wish to use prior to starting the VoltDB process. For example, The following commands start the VoltDB server with the DR network traffic DSCP priority set to 3: $ export VOLTDB_OPTS="-DDR_SOCKET_TRAFFIC_CLASS=3" $ voltdb start -D ~/mydb For Kubernetes, the value can be set using the helm property
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23.6. | Support for Kubernetes 1.21 | |||||||||||||
The latest VoltDB Operator and Helm charts add support for Kubernetes up to version 1.21. The officially supported versions are Kubernetes 1.16.2 through 1.21.x. | ||||||||||||||
23.7. | Additional improvements | |||||||||||||
The following limitations in previous versions have been resolved:
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24. Release V11.0 (August 12, 2021) | ||||||||||||||
VoltDB 11 is a major release incorporating features from recent updates plus new capabilities. It includes the following major new features and improvements. | ||||||||||||||
24.1. | VoltDB Topics | |||||||||||||
VoltDB Topics provide the intelligent streaming of VoltDB's existing import and export capabilities, but with the flexibility of Kafka-like streams. Topics allow for both inbound and outbound streaming to multiple client producers and consumers. They also use the existing Kafka interface to simplify integration into existing infrastructure. But most importantly, they allow for intelligent processing and manipulation of the data as it passes through the pipeline. VoltDB topics, which were released as a beta feature in V10.2, are now ready for production use. See the chapter on Streaming Data in the Using VoltDB manual for more information. | ||||||||||||||
24.2. | Support for Python 3.6 | |||||||||||||
The VoltDB command line tools have been upgraded to use Python version 3. Python 3 is commonly available on modern operating systems and so simplifies the process of configuring platforms for VoltDB. | ||||||||||||||
24.3. | New Kubernetes capabilities | |||||||||||||
Upgrades to the VoltDB Operator for Kubernetes provide two important new features:
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24.4. | VoltDB Java Client improvements | |||||||||||||
The VoltDB Java client interface has been updated with the following improvements:
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24.5. | Security updates | |||||||||||||
The VoltDB Management Center (VMC) web-based console for VoltDB has been updated to the latest versions of the jQuery libraries to address security vulnerabilities. The current library versions for VMC are JQuery v3.5.1 and jQuery-UI v1.12.1. |
The following are known limitations to the current release of VoltDB. Workarounds are suggested where applicable. However, it is important to note that these limitations are considered temporary and are likely to be corrected in future releases of the product.
The following notes provide details concerning how certain VoltDB features operate. The behavior is not considered incorrect. However, this information can be important when using specific components of the VoltDB product.
1. IPv6 | |
1.1. | Support for IPv6 addresses |
VoltDB works in IPv4, IPv6, and mixed network environments. Although the examples in the documentation use IPv4 addresses, you can use IPv6 when configuring your database, making connections through applications, or using the VoltDB command line utilities, such as voltdb and voltadmin. When specifying IPv6 addresses on the command line or in the configuration file, be sure to enclose the address in square brackets. If you are specifying both an IPv6 address and port number, put the colon and port number after the square brackets. For example: voltadmin status --host=[2001:db8:85a3::8a2e:370:7334]:21211 | |
2. Volt Management Center | |
2.1. | Schema updates clear the stored procedure data table in the Management Center Monitor section |
Any time the database schema or stored procedures are changed, the data table showing stored procedure statistics at the bottom of the Monitor section of the VoltDB Management Center get reset. As soon as new invocations of the stored procedures occur, the statistics table will show new values based on performance after the schema update. Until invocations occur, the procedure table is blank. | |
2.2. | TLS/SSL for the HTTPD port on Kubernetes |
Encryption for the httpd port, which VMC uses, is automatically enabled on Kubernetes when you enable TLS/SSL
for the server using the | |
3. SQL | |
3.1. | You cannot partition a table on a column defined as ASSUMEUNIQUE. |
The ASSUMEUNIQUE attribute is designed for identifying columns in partitioned tables where the column values are known to be unique but the table is not partitioned on that column, so VoltDB cannot verify complete uniqueness across the database. Using interactive DDL, you can create a table with a column marked as ASSUMEUNIQUE, but if you try to partition the table on the ASSUMEUNIQUE column, you receive an error. The solution is to drop and add the column using the UNIQUE attribute instead of ASSUMEUNIQUE. | |
3.2. | Adding or dropping column constraints (UNIQUE or ASSUMEUNIQUE) is not supported by the ALTER TABLE ALTER COLUMN statement. |
You cannot add or remove a column constraint such as UNIQUE or ASSUMEUNIQUE using the ALTER TABLE ALTER COLUMN statement. Instead to add or remove such constraints, you must first drop then add the modified column. For example: ALTER TABLE employee DROP COLUMN empID; ALTER TABLE employee ADD COLUMN empID INTEGER UNIQUE; | |
3.3. | Do not use UPDATE to change the value of a partitioning column |
For partitioned tables, the value of the column used to partition the table determines what partition the row belongs to. If you use UPDATE to change this value and the new value belongs in a different partition, the UPDATE request will fail and the stored procedure will be rolled back. Updating the partition column value may or may not cause the record to be repartitioned (depending on the old and new values). However, since you cannot determine if the update will succeed or fail, you should not use UPDATE to change the value of partitioning columns. The workaround, if you must change the value of the partitioning column, is to use both a DELETE and an INSERT statement to explicitly remove and then re-insert the desired rows. | |
3.4. | Ambiguous column references no longer allowed. |
Starting with VoltDB 6.0, ambiguous column references are no longer allowed. For example, if both the Customer and Placedorder tables have a column named Address, the reference to Address in the following SELECT statement is ambiguous: SELECT OrderNumber, Address FROM Customer, Placedorder . . . Previously, VoltDB would select the column from the leftmost table (Customer, in this case). Ambiguous column references are no longer allowed and you must use table prefixes to disambiguate identical column names. For example, specifying the column in the preceding statement as Customer.Address. A corollary to this change is that a column declared in a USING clause can now be referenced using a prefix. For example, the following statement uses the prefix Customer.Address to disambiguate the column selection from a possibly similarly named column belonging to the Supplier table: SELECT OrderNumber, Vendor, Customer.Address FROM Customer, Placedorder Using (Address), Supplier . . . | |
4. Runtime | |
4.1. | File Descriptor Limits |
VoltDB opens a file descriptor for every client connection to the database. In normal operation, this use of file descriptors is transparent to the user. However, if there are an inordinate number of concurrent client connections, or clients open and close many connections in rapid succession, it is possible for VoltDB to exceed the process limit on file descriptors. When this happens, new connections may be rejected or other disk-based activities (such as snapshotting) may be disrupted. In environments where there are likely to be an extremely large number of connections, you should consider increasing the operating system's per-process limit on file descriptors. | |
4.2. | Use of Resources in JAR Files |
There are two ways to access additional resources in a VoltDB database. You can place the resources in the
LOAD CLASSES is used primarily to load classes associated with stored procedures and user-defined functions. However, it will also load any additional resource files included in subfolders of the JAR file. You can remove classes that are no longer needed using the REMOVE CLASSES directive. However, there is no explicit command for removing other resources. Consequently, if you rename resources or move them to a different location and reload the JAR file, the database will end up having multiple copies. Over time, this could result in more and more unnecessary memory being used by the database. To remove obsolete resources, you must first reinitialize the database root directory, start a fresh database, reload the schema (including the new JAR files with only the needed resources) and then restore the data from a snapshot. | |
4.3. | Servers with Multiple Network Interfaces |
If a server has multiple network interfaces (and therefore multiple IP addresses) VoltDB will, by default, open ports on all available interfaces. You can limit the ports to an single interface in two ways:
Also, when using an IP address to reference a server with multiple interfaces in command line utilities (such as voltadmin stop node), use the @SystemInformation system procedure to determine which IP address VoltDB has selected to identify the server. Otherwise, if you choose the wrong IP address, the command might fail. | |
5. Platforms | |
5.1. | OpenShift and Transparent Huge Pages (THP) |
For production, VoltDB requires that Transparent Huge Pages (THP) are disabled because they interfere with memory-intensive applications. However, THP may be enabled on OpenShift containers and the containers themselves not have permission to disable them. To overcome this situation, you must run the Helm chart for disabling THP from a privileged container: $ helm -n kube-system install thp voltdb/transparent-hugepages \ --set thp.securityContext.privileged=true | |
5.2. | Kubernetes Compatibility |
See the Volt Kubernetes Compatibility Chart for information on which versions of the Volt Operator and Helm charts support which version of VoltDB. See the VoltDB Operator Release Notes for additional information about individual releases of the VoltDB Operator. |