http://embeddedgurus.com/barr-code/2008/03/rtos-myth-2-rma-is-for-academics/ A Blog by Michael Barr Tue, 24 Jan 2012 21:58:05 +0000 hourly 1 http://wordpress.org/?v=3.2.1 http://embeddedgurus.com/barr-code/2008/03/rtos-myth-2-rma-is-for-academics/comment-page-1/#comment-32 Andrew Mon, 09 Mar 2009 15:57:00 +0000 http://www.gfcdev.org/test-stack/2008/03/06/rtos-myth-2-rma-is-for-academics/#comment-32 I've previously worked for a company selling a DMA (= Deadline Monotonic Analysis) solution, a close relative of RMA. The key piece of information that's really needed to do RMA or DMA is Worst-Case Execution Time (WCET). Funnily enough, I now work for a company that sells a WCET solution. www.RapitaSystems.com if you're interested. I’ve previously worked for a company selling a DMA (= Deadline Monotonic Analysis) solution, a close relative of RMA. The key piece of information that’s really needed to do RMA or DMA is Worst-Case Execution Time (WCET). Funnily enough, I now work for a company that sells a WCET solution. http://www.RapitaSystems.com if you’re interested.

]]> http://embeddedgurus.com/barr-code/2008/03/rtos-myth-2-rma-is-for-academics/comment-page-1/#comment-31 Michael Barr Fri, 06 Mar 2009 19:24:00 +0000 http://www.gfcdev.org/test-stack/2008/03/06/rtos-myth-2-rma-is-for-academics/#comment-31 Here's an example of the misconception in action. A professor at Vanderbilt University teaches a course about embedded systems, in which he states (slide 6 at the PDF linked below) that a system utilizing 68% or less of the CPU's cycles is "Safe" and acceptable for a "High Consequence" system.http://eecs.vanderbilt.edu/Courses/ee276/Fall06_lectures/02%20Events%20and%20determinism.pdfThe percentage 68% is ONLY meaningful IF the rate monotonic algorithm has been used to prioritize the tasks and the worst-case analysis is properly done. Here’s an example of the misconception in action. A professor at Vanderbilt University teaches a course about embedded systems, in which he states (slide 6 at the PDF linked below) that a system utilizing 68% or less of the CPU’s cycles is “Safe” and acceptable for a “High Consequence” system.http://eecs.vanderbilt.edu/Courses/ee276/Fall06_lectures/02%20Events%20and%20determinism.pdfThe percentage 68% is ONLY meaningful IF the rate monotonic algorithm has been used to prioritize the tasks and the worst-case analysis is properly done.

]]>