McObject

eXtremeDB from McObject is an in-memory and/or persistent database system that
offers an ultra-small footprint (starting at 200KB) and provides performance
benefits for both embedded systems and server development.  eXtremeDB
pioneered the in-memory embedded database market and is the database system
leader for embedded system (IoT) development.  With its core
in-memory database system (IMDS) architecture, eXtremeDB delivers the real-time responsiveness demanded in
applications that cannot tolerate the latency of on-disk database systems. eXtremeDB scales to terabytes, as either an in-memory or a
persistent database system.

eXtremeDB is offered on all major server and
real-time operating systems (RTOSs), and can even run without an OS in
“bare bones boards” configurations. It is exceptionally portable, due
to a design that eliminates dependencies on OS-specific features. Source code
is available.

Thousands of
software developers have worked with eXtremeDB, and the database system plays key
roles in more than 28 million deployed applications, ranging from consumer
electronics to networking gear, mission critical avionics, industrial
controllers, medical technology and more. McObject customers include Sandvine, F5
Networks, BAE Systems, Kapsch Group, EADS, Mettler-Toledo, Siemens, Phillips,
Motorola, JVC, GoPro, and many others.