Tips for Optimizing Linux Memory Usage
If you ran the command line described earlier, one of your largest binaries was probably the X server. The X Window system takes a lot of memory resources.
The first question to consider is, do you really need to run X? Using the virtual consoles and selection service you can have multiple windows supporting cut & paste of text using a mouse. Particularly while performing large compiles (such as the kernel), you should consider the option of simply not running X.
There is also a windowing system called “mgr” than can be used as an alternative to X, but requires less memory.
If you decide to use X, then you can obtain replacements for some of the standard tools that require less resources. “Rxvt” is similar to xterm, but requires significantly less memory. The window manager “fvwm” will also use less resources than others, and “rclock” is a small X-based clock program. These three tools, written by Robert Nation, can make running X feasible on a machine that constantly swapped before.
How many programs do you run on the X desktop? Run “top” to see how much memory is being taken by xclock, xeyes, xload, and all those other goodies you think you need.
The “Tiny X” package, put together by Craig I. Hagan, contains the Korn shell, fvwm window manager, rxvt, rclock, X server, and the minimum of other files needed to run X. The package is small enough to fit on one 3.5" floppy disk. Also included are some useful notes on saving memory under X.
With the techniques described here, you can run small X applications reasonably well on a machine with only 4 megabytes of memory. On machines with more memory, the same methods will allow you to run larger applications and free up memory to use for disk buffering.
By combining the techniques I've described, the net effect on system performance can be well worth the effort. I encourage you to experiment, and along the way you'll almost certainly learn something new.
The software mentioned in this article is available on a number of Internet archive sites, including sunsite.unc.edu and tsx-11.mit.edu. I suggest getting a copy of the Linux Software Map to help track down the software you need.
If you want to learn more about how the Linux kernel implements memory management, check out ”The Linux Kernel Hackers' Guide“, by Michael K. Johnson, part of the Linux documentation project. Appendix A of that document includes an extensive bibliography of books covering operating system concepts in general.
”How to Maximize the Performance of X" is periodically posted to the Usenet newsgroup news.answers, and contains more ideas for improving X performance on small systems.
Fast/Flexible Linux OS Recovery
On Demand Now
In this live one-hour webinar, learn how to enhance your existing backup strategies for complete disaster recovery preparedness using Storix System Backup Administrator (SBAdmin), a highly flexible full-system recovery solution for UNIX and Linux systems.
Join Linux Journal's Shawn Powers and David Huffman, President/CEO, Storix, Inc.
Free to Linux Journal readers.Register Now!
- Download "Linux Management with Red Hat Satellite: Measuring Business Impact and ROI"
- Sony Settles in Linux Battle
- Peppermint 7 Released
- Libarchive Security Flaw Discovered
- Profiles and RC Files
- Maru OS Brings Debian to Your Phone
- The Giant Zero, Part 0.x
- Snappy Moves to New Platforms
- Git 2.9 Released
- Astronomy for KDE
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