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eXtremeDB In-Memory Database System paired with ThreadX RTOS in technology alliance for deeply embedded systems. Get details.

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Benchmark: McObject & EMC technologies combine to boost in-memory database speed, durability & scalability. Read the
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Compass-EOS integrates eXtremeDB High Availability DBMS in breakthrough photonics-based core router. Learn more.

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Printable Version

Key eXtremeDB Features


eXtremeDB Embedded Database Architecture

Core In-Memory Database System (IMDS) Design
Tiny Footprint (Approximately 150K)
Optional On-Disk or Hybrid Storage

Powerful Run-Time Features

ACID Transactions High Availability and Clustering
Transaction Logging 64-Bit Support
Multi-Version Concurrency Control (MVCC) Open Replication
Cache Prioritization Event Notifications
Deterministic Rule-Based SQL Optimizer Pattern Search
Security Features Binary Schema Evolution
Remote Procedure Calls (RPCs) Database Striping/Mirroring
XML Import/Export Kernel Mode Deployment

Unmatched Developer Flexibility

C/C++, SQL, Java, C# APIs B-Tree, R-Tree, Patricia Trie, KD-Tree and Hash Indexes
Wide Range of Supported Data Types Designed To Prevent Database Corruption
Custom Collations Broad Platform Support
Source Code Available Proven Solution
Unmatched Developer Support  


The eXtremeDB Embedded Database, Feature-By-Feature:

Core In-Memory Database System (IMDS) Design

As an in-memory database system (IMDS), eXtremeDB gives your application speed without rewrites or expensive new hardware. It eliminates disk and file I/O, cache management and other sources of latency. By working with data directly in main memory, eXtremeDB avoids the overhead of data duplication and transfer inherent in disk-based DBMSs. Databases can be created in shared memory, enabling concurrent access by multiple processes. Read about the performance advantages of IMDS technology in the white papers offered from this site.

Tiny Footprint (Approximately 150K)

Small code size and minimal overhead (database system memory footprint is as small as 15% of managed data volume) means less RAM is required; eXtremeDB’s streamlined design permits a lower cost CPU. As a result, your design can use less expensive hardware, resulting in lower manufacturing costs. Or, use the extra CPU speed to offer a snappier user experience than your competition, and use the extra memory to manage more data at the same cost as competing products.

Optional On-Disk or Hybrid Storage

In addition to the core eXtremeDB in-memory data storage, McObject's eXtremeDB Fusion edition adds hybrid storage: certain record types can be designated for on-disk storage, with flexible caching. Choose the best storage medium based on performance, persistence, cost and form factor.  

High Availability and Clustering

Committed to 99.999% uptime or better? eXtremeDB High Availability (HA) edition ensures continuous database operation even in the face of hardware or software failure. eXtremeDB HA supports both synchronous (2-safe) and asynchronous (1-safe) replication, with automatic failover.

In distributed architectures based on eXtremeDB Cluster, every database instance serves as a master. Any process on any node can update its local database, and Cluster efficiently replicates changes to other nodes. Clustering can dramatically increase available net processing power, lower system expansion costs (by enabling use of low-cost “commodity” hardware), and maximize scalability and reliability for data-intensive applications.

ACID Transactions

eXtremeDB’s transactions support the ACID (Atomic, Consistent, Isolated and Durable) principles, which safeguard data integrity by guaranteeing that updates will complete together or the database will roll back to a pre-transaction state. eXtremeDB also enables the developer to prioritize transactions.

64-bit Support

The 64-bit edition of eXtremeDB scales to support databases that are terabytes in size, to address the real-time database needs of financial, social network, object-caching and other highly scalable applications.

In a published benchmark test, an eXtremeDB-64 database grew to 1.17 terabytes and 15.54 billion rows, with no apparent limits on it scaling further. Performance remained consistent as the database size increased, suggesting nearly linear scalability. For a simple SELECT against the fully populated database, eXtremeDB-64 processed 87.78 million query transactions per second using its native application programming interface (API) and 28.14 million transactions per second using a SQL ODBC API.

Multi-Version Concurrency Control (MVCC)

Another important tool for scalability is eXtremeDB's optional Multi-Version Concurrency Control (MVCC) transaction manager, which is available as an alternative to the "pessimistic" database locking of the original eXtremeDB MURSIW (MUltiple Reader, SIngle Writer) transaction manager. MVCC can dramatically improve scalability and performance, especially in applications with on-disk or hybrid (in-memory and on-disk) database storage; many tasks or processes concurrently modifying the database (versus read-only); and in multi-core systems.

Transaction Logging

eXtremeDB Transaction Logging edition adds recoverability by writing database changes into a transaction log on persistent media. Logging may be set to different levels of transaction durability, allowing system designers to make intelligent trade-offs between performance and risk of unrecoverable transactions.

Open Replication

McObject's eXtremeDB Data Relay technology facilitates seamless, fine-grained data sharing between real-time systems based on eXtremeDB, and external systems such as enterprise DBMSs. As part of the eXtremeDB Transaction Logging edition, Data Relay helps developers by simplifying the code that “looks inside” database transactions for changes that should be relayed. It also guarantees maximum efficiency by eliminating the CPU-intensive task of monitoring database activity. Sharing of data can be either synchronous or asynchronous.

Cache Prioritization

eXtremeDB Fusion improves on typical Least Recently Used (LRU) cache policies by allowing applications to influence how long certain pages remain in cache, to minimize retrieval overhead for objects used in time-sensitive tasks. When considering whether to remove a page from the cache, eXtremeDB's LRU algorithm examines the cache priority property set for the page; the higher the priority, the longer the page remains linked to the LRU list (stays in cache). A caching priority of zero is the default.

Event Notifications

Similar to triggers in a relational database management system, this feature enables eXtremeDB to notify an application when something "of interest" in the database changes. It is available in synchronous and asynchronous modes.

Deterministic Rule-Based SQL Optimizer

Cost-based SQL optimizers must collect sample data, generate statistics and analyze thousands -- sometimes hundreds of thousands -- of possible execution plans; these requirements make cost-based optimizers' operation CPU-intensive and unpredictable. In contrast, eXtremeSQL (eXtremeDB's SQL interface) uses a highly efficient and predictable rule-based optimizer.

Pattern Search

For flexibility in querying, eXtremeDB supports the use of wildcards to search tree index entries for single and multiple character matches.

Security Features

eXtremeDB protects your database. Cyclic Redundancy Check (CRC) on the database page level detects whether unauthorized modification to stored data has occurred, while RC4 encryption employs a user-provided cipher to prevent access or tampering. In addition to safeguarding sensitive data (in financial or defense systems, for example) page-level CRC can be used in devices such as portable audio players to help enforce digital rights management.

Binary Schema Evolution

eXtremeDB can save a database as a binary image and then restore it with a changed schema. This can accomplish design changes more quickly, using less memory and storage, than the alternative approach using XML import/export.

Remote Procedure Calls (RPCs)

eXtremeDB generates an interface that enables remote processes (i.e. on another network node) to read/update an eXtremeDB database.

Database Striping/Mirroring

eXtremeDB Fusion can exploit multi-disk (solid state or spinning) configurations with its support for RAID-like data striping and data mirroring. Striping accelerates performance when working with two or more disks by parallelizing access to data. Mirroring provides continuous backup by replicating data onto separate disks (if disk A fails, identical records are available from disk B).

XML Import/Export

eXtremeDB's schema compiler, mcocomp, can generate XML interface functions for each class, providing the means to retrieve an object encoded as XML, to create or replace (update) an object in the database from the content of an XML string, to generate the XML schema for each class in the database in order to facilitate sharing data with other XML-enabled systems, and to accomplish simple eXtremeDB schema evolution.

Kernel Mode Deployment

McObject pioneered the concept of an in-memory database that deploys in the operating system kernel. eXtremeDB Kernel Mode leverages the high priority, zero-latency responsiveness afforded to kernel tasks—and meets the data sorting, access and retrieval needs of applications that place key functions there.

C/C++, SQL, Java APIs

eXtremeDB provides the developer with multiple application programming interfaces (APIs). Access eXtremeDB using a fast, native navigational API consisting of C/C++ functions. This is provided as both a type-safe and intuitive application-specific API (functions are generated based on the data design), and as a uniform data access (UDA) API for a consistent interface across all projects. eXtremeDB’s SQL implementation includes an ODBC API for interoperability, a more succinct and easier to use proprietary API, and a type 3, version 4 JDBC driver. eXtremeDB’s Java Native Interface (JNI) and C# native interface offer the fastest possible DBMS solutions in these languages, and the ability to access eXtremeDB while working entirely with "plain old" Java and C# objects.

Designed To Prevent Database Corruption

The eXtremeDB native API is type-safe: errors in data-typing are caught at compile time, to eliminate database corruption. In addition, the eXtremeDB runtime implements many verification traps and consistency checks. After application debugging, the optimized version of the eXtremeDB runtime can be used, removing traps and internal checks, and restoring valuable clock cycles.

In addition, cyclic redundancy check is built into the backup-and-restore feature for in-memory databases, executing automatically when a file is loaded to ensure the database was written in its entirety when saved, and has not been corrupted.

B-Tree, R-Tree, Patricia Trie, KD-Tree and Hash Indexes

eXtremeDB provides a wide range of database indexes, to boost application performance and minimize footprint. eXtremeDB offers R-trees for geospatial data, Patricia tries for IP/telecom, KD-trees for multi-dimensional data and Query-by-Example (QBE), B-trees, hash indexes and more. For in-memory databases, rather than storing duplicate data, indexes contain only a reference to data, keeping memory requirements to an absolute minimum.

Wide Range of Supported Data Types

eXtremeDB supports a wide range of data types -- including structures, arrays, vectors and BLOBs -- for maximum coding efficiency. Data can be stored in the same complex form in which it is used in the application, or as normalized relations.

Custom Collations

eXtremeDB includes hooks that enable developers to provide a desired character sorting sequence (collation) for data stored as text, including collation that supports a particular language or combination of languages. A single application can support search and other text-processing functions in multiple languages.

Broad platform support

eXtremeDB operates on multiple platforms including all major server and real-time operating systems (RTOSs), and can even run without an OS in "bare bones boards" configurations. It is designed to minimize reliance on OS-specific features, in order to simplify the task of porting to new operating systems.

Source code available

Available source code provides the ultimate transparency for developers using eXtremeDB. Use it for porting, learning, or to add a needed function.

Proven Solution

Compared to self-developed (‘homegrown’) data management, eXtremeDB offers a proven solution that slashes months from development, QA and ongoing support. Why take on the complexity and cost of developing a database management system from scratch, when an off-the-shelf solution meets your requirements?

Unmatched Developer Support

McObject technical support engineers are database and real time application experts who  answer customer questions in detail. Whether embedded systems beginners with basic configuration questions or seasoned developers looking for hints on optimization, customers get prompt, informative answers and continued follow-up to speed production and get the most from eXtremeDB.