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. At present, eXtremeDB/rt is available for Azure RTOS ThreadX, Deos™ from DDC-I, embOS® from SEGGER, FreeRTOS™ from Amazon, Green Hills Software INTEGRITY, LynxOS®, SIEMENS’ Nucleus® and WindRiver’s VxWorks®, all on select hardware. In addition, eXtremeDB/rt functionality can be evaluated in the context of a non-real-time OS — Linux, MacOS, and Microsoft Windows with the understanding that real-time provisions may be compromised by those non-real-time OS.
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.