SAN DIEGO--Express Logic, Inc., the worldwide leader in royalty-free, real-time operating systems (RTOS), is scheduled to present details of its Preemption-Threshold Scheduling (PTS) in a class at Embedded World 2012 in Nuremberg, Germany. Although preemption is how real-time systems guarantee responsiveness to time-critical events, Express Logic has devised a way to minimize the number of preemptions, while preserving the systems' schedulability. Academic research has shown that systems implementing PTS can gain a 20-30% increase in performance and a 30–35% reduction in stack size, while still meeting schedulability demands.

“Preemption-threshold scheduling ensures the application can meet those real-time deadlines using the least number of context switches possible. Academic research has proven that such refinements boost system performance while reducing memory—two features that may explain the enormous success the ThreadX RTOS enjoys.”

Technical Session Details:

• Paper title—Meet Hard Real-Time Deadlines with Reduced Overhead Through Preemption-Threshold Scheduling (PTS)
• Presenter—John Carbone, VP of Marketing
• Time—Wednesday, February 29^th from 11:00–11:45 A.M. (session 11)
• Description: Real-time embedded systems typically use a collection of independent tasks or threads that must complete their work before a certain deadline. Hard real-time systems demand that all deadlines be met with absolute certainty, even under worst-case conditions. To do this, real-time systems use preemptive scheduling which guarantees that the most critical threads get immediate attention, enabling them to meet their deadlines. However, preemptive scheduling can result in significant context-switch overhead. Preemption-Threshold Scheduling (PTS) reduces the number of context switches in a real-time system by inhibiting preemption for a thread-specific range of priorities. Developers can elect where and when to use PTS, and otherwise use traditional, fully preemptive scheduling. Research findings on PTS will demonstrate how PTS is optimal among all preemption-limiting methods for boosting application performance, minimizing a system's total stack memory requirements and avoiding priority inversion.

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“Many applications demand very fast, very responsive applications,” confirmed William E. Lamie, founder and CEO of Express Logic. “Preemption-threshold scheduling ensures the application can meet those real-time deadlines using the least number of context switches possible. Academic research has proven that such refinements boost system performance while reducing memory—two features that may explain the enormous success the ThreadX RTOS enjoys.”

Express Logic's ThreadX RTOS is a small, fast, royalty-free RTOS that provides the priority-based preemptive scheduling, optimized context switching, and an intuitive, easy-to-use API. ThreadX has been deployed in over 1 billion electronic products in areas such as consumer electronics, medical devices and industrial-control systems—where fast, efficient and high performance is essential.

A demonstration of Express Logic's ThreadX RTOS, which features Preemption-Threshold Scheduling, can be viewed at the Express Logic booth in Hall 5, Stand 320.

About Express Logic and ThreadX

Headquartered in San Diego, CA, Express Logic offers the most advanced run-time solution for deeply embedded applications, including the popular ThreadX® RTOS, the high-performance NetX™ TCP/IP stack, the FileX™ embedded MS-DOS-compatible file system, and the USBX™ Host/Device USB protocol stack. All products from Express Logic include full source code and have no run-time royalties. For more information about Express Logic solutions, please visit the Web site at www.expresslogic.com, call 1-888-THREADX, or e-mail inquires to info@expresslogic.com.

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ThreadX, TraceX, and FileX are registered trademarks, and Certification Pack, NetX, CANX, USBX, StackX, PEGX, preemption-threshold, picokernel, and UDP fast path are trademarks of Express Logic, Inc. All other brands or product names are the property of their respective holders.

Graphics and Word copy of release:
You can tweet and share the release to social media accounts via the Express Logic Press Center on HCI's website. Graphics and other background materials are available for download.

Caption for Graphic:
Research shows PTS reduces preemptions by up to 30% leading to a 20-30% increase in performance and a 30–35% reduction in stack size.