Real-Time Linux Kernel Scheduler
The most important goal of a real-time kernel scheduler is to ensure SWSRPS. The scheduler in the CONFIG_PREEMPT_RT kernel uses push and pull algorithms to balance and correctly distribute real-time tasks across the system. Both the push and pull operations try to ensure that a real-time task gets an opportunity to run as soon as possible. Also, in order to reduce the performance and scalability impact that might result from increased contention of global variables, the scheduler uses the concept of root domains and CPU priority management. The scope of the global variables is reduced to a subset of CPUs as opposed to the entire system, resulting in significant reduction of cache penalties and performance improvement.
This work represents the views of the author and does not necessarily represent the view of IBM. Linux is a copyright of Linus Torvalds. Other company, product and service names may be trademarks or service marks of others.
Index of /pub/linux/kernel/projects/rt (Ingo Molnar): www.kernel.org/pub/linux/kernel/projects/rt
[patch] Modular Scheduler Core and Completely Fair Scheduler [CFS] (Ingo Molnar): lwn.net/Articles/230501
Multiprocessing with the Completely Fair Scheduler, Introducing the CFS for Linux: www.ibm.com/developerworks/linux/library/l-cfs/index.html
RT Wiki: rt.wiki.kernel.org
Ankita Garg, a computer science graduate from the P.E.S. Institute of Technology, works as a developer at the Linux Technology Centre, IBM India. She currently is working on the Real-Time Linux Kernel Project. You are welcome to send your comments and suggestions to email@example.com.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
Free to Linux Journal readers.Register Now!
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- SUSE LLC's SUSE Manager
- My +1 Sword of Productivity
- Managing Linux Using Puppet
- Non-Linux FOSS: Caffeine!
- Tech Tip: Really Simple HTTP Server with Python
- SuperTuxKart 0.9.2 Released
- Parsing an RSS News Feed with a Bash Script
- Doing for User Space What We Did for Kernel Space
- Google's SwiftShader Released
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide