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eXtremeDB/rt Questions and Answers

We hope this answers your questions about eXtremeDB/rt.  If you have any further questions about it, or would like to get a free trial, please contact us.

Q) What is eXtremeDB/rt?

A)  eXtremeDB/rt is the first and only commercial, supported, embedded deterministic database management system. eXtremeDB/rt enforces database transaction deadlines through time-cognizant transaction managers.

Q) Do ACID properties apply to eXtremeDB/rt?

A)  Yes, in addition to supporting time-cognizant transactions, the eXtremeDB/rt transaction manager (or transaction scheduler) fully supports database ACID (atomicity, consistency, isolation, and durability) properties.

Q) What class of applications benefit from using eXtremeDB/rt?

A)  eXtremeDB/rt is designed for mission critical and safety critical hard-real-time applications. Examples include avionics and aircraft navigation systems, driver assistance systems, medical equipment, railway systems, medical systems and energy systems.

Q) What storage media does eXtremeDB/rt support?

A)   At present, eXtremeDB/rt supports in-memory databases. In persistent database systems, the response time of transactions are determined not only by CPU load, but also by I/O latency, which adds to the complexity of real-time database kernel algorithms. That said, supporting databases in persistent secondary storage such as high-capacity flash memories, which is increasingly common in modern embedded systems, is vitally important for real-time systems’ developers. eXtremeDB/rt kernel will soon be extended with algorithms that are “I/O aware” to guarantee transaction response times in the presence of persistent media.

Q) A search of the internet for ‘real-time database’ is dominated by systems that provide real-time analytics. What is the difference between those products and eXtremeDB/rt?

A)  This is about an approach to getting analytics on data as it is being streamed into the database, as opposed to having to execute queries against the database after the data has been ingested. In this context, the terms “real-time” and “fast” are synonymous (and subjective). In contrast, eXtremeDB/rt is a true real-time DBMS that supports time-cognizant transaction managers on a number of real-time operating systems and hardware platforms. Through the enforcement of transaction deadlines, eXtremeDB/rt is objectively real-time.

Q) What operating systems is eXtremeDB/rt available for?

A)  In order to satisfy hard-real time requirements, the eXtremeDB/rt target applications must run in the context of a real-time operating system or have direct access to hardware resources such as interrupts, and timers.

Download a trial today

Deos™DDC-INXP® iMX8QuadMaxEmbedded
embOSSEGGERSTM32F769 (STMCube)Embedded
FreeRTOS™AmazonARM family including STM32F769, STM32F750N8 and NXPEmbedded
iMX8QuadXPlus/QuadMax Cortex-MEmbedded
INTEGRITY®Green Hills SoftwareARM familyEmbedded
LinuxARM familyEmbedded
x86_64Desktop evaluation
LynxOS-178®Lynx Software Technologiesx86_64Embedded
macOSApplex86_64/ARMDesktop evaluation
MICROSARVectorNXP iMX8QuadXPlus Cortex-MEmbedded
Microsoft® Windows®MicrosoftVisual Studio 2017, x64Desktop evaluation
Nucleus®SiemensARM familyEmbedded
PetaLinux 2019.1AMD XilinxZynq™ UltraScale+™ MPSoC ZCU104 with   ARM-A53Embedded
QNX® 7.0/7.1Blackberry®ARM family including NXP iMX8QuadXPlus/QuadMax Cortex-AEmbedded
x86_64Desktop evaluation
ThreadX (AzureOS)MicrosoftSTM32F769Embedded
NXP RT1060Embedded
VxWorks®Wind River®ARM familyEmbedded
Q) Is eXtremeDB/rt available for the certified versions of the operating systems mentioned above?

A)  Yes, for some. At present, eXtremeDB/rt is available for Deos, LynxOS-178B, VxWorks 653 and INTEGRITY 178B (on select hardware).

Q) How can we evaluate eXtremeDB/rt?

A)  The nature of eXtremeDB/rt’s tight integration with the RTOS and target hardware requires that each evaluation package be assembled uniquely for your needs. Please contact us so that we can gather information on your RTOS vendor, version, target hardware, tool chain, and so on.

If you would like to get an overview of eXtremeDB/rt outside of an RTOS, “desktop” evaluation packages are available for immediate download for Linux (any Intel® 64 architecture), MacOS and Microsoft Windows (VS2017, any Intel® 64 architecture) platforms. The desktop distributions include numerous samples that demonstrate the eXtremeDB/rt API.

You are also welcome to contact us, and we will send you a download of eXtremeDB/rt running in the FreeRTOS simulator.

Q) How is eXtremeDB/rt licensed?

A)  As eluded to in the previous answer, eXtremeDB/rt is always licensed with complete source code, and for specific target systems. It is an annual subscription for which the amount is determined by the number and type of target systems and development team size, and includes technical support and software maintenance.

Related Resources

Documentation & Collateral


Review the eXtremeDB/rt data sheet


Learn more about eXtremeDB/rt in our on-line documentation

To Err is Human. The Case for Buy Over Build in Hard Real-time Database Management Systems

In the News

Buy vs. Build for Time-Critical Sensor Data May 2, 2024

Word art surrounding hard real-time DBMS

Tailored to your needs

The nature of eXtremeDB/rt’s tight integration with the RTOS and target hardware requires that each evaluation package be assembled uniquely for your needs.  Please contact us so that we can gather information on your RTOS vendor, version, target hardware, tool chain, and so on.

View the ever-expanding list of supported real-time operating systems.

Review the platforms

Send us an email

Give us a call


Desktop distributions

Free desktop evaluation packages of eXtremeDB/rt for Linux, MacOS and Windows platforms are available for immediate no-hassle download. Learn more about the programming interface and various real-time and non-real-time features of eXtremeDB/rt. After you have tried the desktop version, we hope you’ll contact us for a free trial of eXtremeDB/rt tailored to the needs of your RTOS.

You are also welcome to try eXtremeDB/rt running in the FreeRTOS Linux/POSIX simulator.

eXtremeDB/rt for Linux

eXtremeDB/rt for MacOS

eXtremeDB/rt for Windows

Real-time database

“Real-time database” has come to have two meanings.  The first and, so far, the predominant use of the term refers to a database system which uses streaming technologies to handle workloads for which the state changes in real-time as a reflection of real-world events. This differs from traditional databases containing persistent data, mostly unaffected by time. In this context, real-time processing means that a transaction is processed fast enough for the result to come back and be acted on right away. Such real-time databases are useful for fraud detection, recommendation engines, audience targeting, and pricing strategies.

The other use of the term “real-time database” embodies a more strict definition of real-time. A hard real-time database system is one that is time cognizant: It is aware of processing deadlines and offers transaction schedulers that enforce those deadlines and are adaptable to varying workloads (e.g., works equally well with periodic and aperiodic tasks) and changing deadlines and task priorities. This is the only type of database management system that, when used with a RTOS, is acceptable for use in mission- and safety-critical systems.

Further reading

Deterministic database

“Deterministic database management system” has come to have two meanings.

A deterministic real-time database system guarantees that transactions complete (commit or rollback) within a set deadline. Transactions that are destined to be “late” are identified, interrupted and forced to initiate rollback in time to satisfy set deadlines. The key is to ensure that all database runtime internals are in a “recoverable” condition.

In the context of distributed systems, deterministic can mean that changes are organized up front, and then applied. For example, geographically distributed replicas (or shards) can be given the same input and be guaranteed to produce the same result, making data replication (and replay) easier to implement.

Further reading

electronic design article, Real-time database systems are not actually real-time. Unless they are.
COTS article about eXtremeDB/rt

Keeping A Mission-Critical Deterministic DBMS On Time” by McObject CTO Andrei Gorine, September 20, 2021

News and articles about real-time database management.

Chart of transaction timelines for conventional and real-time databases in several scenarios.
"Buy vs. Build for Time-Critical Sensor Data Fusion" May 2, 2024
COTS Cover photo July 2022

"Soft v Hard Real-time Systems" Embedded Computing, November 4, 2022

Real-time transaction timeline

"Embedded Databases in Real-Time Systems", March 14, 2022

Steve Graves, President and CEO, McObject

"Embedded Executive: Steve Graves, President and CEO, McObject", January, 2022 An interview reviewing key concepts in real-time computing.

COTS article about eXtremeDB/rt

"Databases in Hard Real Time" McObject Launches True Real-Time Deterministic Database for embOS Real-time Operating System Applications,, October 15, 2021

COTS article about eXtremeDB/rt

"Keeping A Mission-Critical Deterministic DBMS On Time" by McObject CTO Andrei Gorine, September 20, 2021

COTS article about eXtremeDB/rt

"Real time tasks need real time data" Read the Wind River blog, September 7, 2021

We're grateful for the partnerships we have with industry leaders, and invite you to read what they say about eXtremeDB/rt in our joint press releases.

Azure logo

Azure RTOS ThreadX

“Managing data with a hard real-time requirement is a challenge for developers,” comments Tony Shakib, Partner General Manager, Microsoft Azure IoT. “Developers have had to use current solutions that may not meet time constraints or write their own database system. eXtremeDB/rt brings a solution to Microsoft Azure developers that eliminates this trade off.”

Read the joint press release.

Azure logo

DDC-I’s Deos

eXtremeDB/rt provides an excellent option for developers of resource-constrained, mission-critical embedded systems who require a compact, real-time embedded database,” said Greg Rose, vice president of marketing and product management at DDC-I. “We look forward to working with McObject to offer eXtremeDB/rt to embedded developers utilizing our Deos real-time operating system.”

Read the joint press release.


embOS from SEGGER

SEGGER’s CEO, Ivo Geilenbruegge, had this to say: “We are excited that McObject has created a first-of-its-kind real-time database system to complement our embOS RTOS and extend support for hard real-time systems to include database operations. Real-time systems are following the trend of embedded systems in that they are being called upon to manage more (and more complex) data."

Read the joint press release.

FreeRTOS logo


Richard Barry, FreeRTOS founder, said “It is good to have another high-quality option for FreeRTOS users, this time providing a real-time deterministic database which can, as just one example, fulfill a crucial role in the Industrial Internet of Things (IIoT): data collection, aggregation, and distribution in oil rig blow-out prevention (BOP) systems. A BOP is a specialized device equipped with sensors to detect a “kick” and actuate valves to prevent a catastrophic blowout.” Richard continued, “The need to detect and respond within deadlines is emblematic of real-time industrial systems.”

Read the press release.

FreeRTOS logo

INTEGRITY from Green Hills Software

Joe Fabbre, Global Technology Director for Green Hills had this to say: “McObject has created a unique real-time database that complements our INTEGRITY RTOS and extends hard real-time support to database operations. Advanced applications in real-time systems are being called upon to manage more (and more complex) data. eXtremeDB/rt gives developers of these systems an off the shelf solution for real-time data management.”

Read the joint press release.

FreeRTOS logo


“We were delighted to work with McObject to bring eXtremeDB/rt to the LynxOS partner ecosystem. Our companies share the vision that real-time systems are becoming more sophisticated and consequently have to manage more complex data. eXtremeDB/rt fills a critical gap in the technology stack,” said Pavan Singh, VP of product management, Lynx Software Technologies.

Read the joint press release.

PX5 RTOS logo


“This integration will empower developers to focus on building their applications without worrying about the underlying data management layer.”

Read the joint press release.

Blackberry QNX logo

QNX Neutrino RTOS

“Real-time performance can benefit embedded software developers in many market segments including autonomous systems, industrial control, robotics and medical devices,” said Romain Saha, Strategic Alliances Director at BlackBerry QNX: “McObject builds upon many years of QNX support by bringing eXtremeDB/rt to the latest version of the QNX Software Development Platform.”

Read the joint press release.

Siemens 2022 logo


“McObject’s eXtremeDB/rt allows Nucleus customers to have a truly embedded database solution that allows them to meet the determinism they require in a commercial-off-the-shelf solution.” said Jeff Hancock, Siemens Embedded Senior Product Manager. “eXtremeDB/rt helps Nucleus customers manage ever-growing data requirements.”

Read the joint press release.

Siemens 2022 logo

WindRiver VxWorks

“Through our work with McObject, we’re helping customers modernize and accelerate the delivery of reliable intelligent systems that demand real-time requirements,” said Michel Chabroux, Senior Director, Product Management, Wind River. “We look forward to building on our proven track record of success with McObject to help advance the next generation of cloud-connected intelligent systems with increasingly challenging edge compute needs.”

Read the joint press release.