Multiheading Linux Systems
Red Hat has a hardware browser application at /usr/bin/hwbrowser that gives useful information. This is handy under X to see if both video cards are recognized by the system.
Some cards just don't get along. We successfully tried a number of combinations—a matched pair of ATI Mach64 3D RAGE II PCI cards, an ATI Mach64 AGP and Matrox II PCI card, and an S3 Virge PCI and NVIDIA Riva TNT2 AGP card. We got those combinations working within minutes using the above procedure. We also unsuccessfully tried a Diamond Stealth II S220, which definitely does not play well with others. We could not get this card to work with another at all.
The primary video card is where the BIOS display appears and is what gets Screen0. The video card on the highest number PCI channel is the primary card. Some computer BIOSes give an option to initialize the AGP card first, but this did not work for us because the PCI card still displayed the BIOS, which is too bad, because that level of control over the environment would be useful.
Since you have multiple screens when you use the KDE login manager, the KDE screensaver only works on the primary screen. Set up xscreensaver and call it in your shell initialization files (.bashrc for example) if you want both screens to have a screensaver. It's easy to put one screensaver on one screen and a different one on the other using :0.0 or :0.1 in the configuration.
Put some variable assignments in .bashrc, such as left='-display :0.1' and right='-display :0.0'. Then you can specify which screen to use, e.g., xeyes $left or xclock $right. It helps make things a little simpler to use.
Our current favorite way to work is to utilize the KDE login and the KDE window environment. KDE seems a little cleaner as a work environment and goes across multiple screens (remember that in configuration two with GNOME, you have to start a second window manager). More importantly, the KDE login gives you separate screens so you can open up one screen for people to use (xhost + to disable access control) and still work on the other without security concerns. Also, we tend to devote one screen to monitoring events and displaying things.
The formula presented here is very simple to follow, and a working Linux system can be converted to multiple displays in under ten minutes, if the video hardware supports it. This technique allowed us to utilize otherwise obsolete hardware to simplify our engineering work greatly.
The authors thank Gary Normandin for his insights and hard work testing these methods, Dennis Baker for pointing the way with his Xinerama HOWTO (found at www.linuxdoc.org) and Learning Tree International for letting us use their equipment for some of the testing.
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.
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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