Language Selection

English French German Italian Portuguese Spanish

Ubuntu 32-bit, 32-bit PAE, 64-bit Kernel Benchmarks

Filed under
Ubuntu

Coming up in our forums was a testing request to compare the performance of Linux between using 32-bit, 32-bit PAE, and 64-bit kernels. This is coming after Linus Torvalds has spoke of 25% performance differences between kernels using CONFIG_HIGHMEM4G and those without this option that allows 32-bit builds to address up to 4GB of physical RAM on a system. We decided to compare the performance of the 32-bit, 32-bit PAE, and 64-bit kernels on a modern desktop system and here are the results.

For this comparison we used Ubuntu 9.10 on a Lenovo ThinkPad T61 notebook running an Intel Core 2 Duo T9300 processor, 4GB of system memory, a 100GB Hitachi HTS7220 SATA HDD, and a NVIDIA Quadro NVS 140M. We were using the Ubuntu-supplied kernels that are based off the Linux 2.6.31 kernel in Ubuntu Karmic. Other packages that were maintained included GNOME 2.28.1, X Server 1.6.4, NVIDIA 195.22 display driver, GCC 4.4.1, and we were using the default EXT4 file-system with all other defaults. With Ubuntu to properly address 4GB or greater of system memory you need to use a PAE kernel as the Physical Address Extension support through the kernel's high-mem configuration options are not enabled in the default 32-bit kernels. CONFIG_HIGHMEM4G is enabled in the default Ubuntu kernel, but the Ubuntu PAE kernel uses CONFIG_HIGHMEM64G (and other build options) for handling up to 64GB of system memory. Of course, with 64-bit addressing there is not this greater than 4GB RAM limitation. Though even with a 32-bit non-PAE kernel the system will only report 3GB of system memory by default due to 1GB of that being reserved for kernel virtual addresses while the 3GB is available to user-space addresses.

rest here




More in Tux Machines

Is Microsoft engaging in digital imperialism?

Windows, the common carrier of Microsoft, is such a sordid mess that it suffers regular glitches and conducts mass surveillance on users. Microsoft knows that without Windows it cannot survive, so dirty tricks resume in a very big way. This is not a beep on the radar but somewhat of a surge. Nothing is going to change in Munich, but Microsoft is trying to maintain an international/universal perception that the migration to GNU/Linux was a disaster. Numerous anonymous blogs were created to attack Munich over this and provocateurs of Microsoft loved citing them, only to be repeatedly proven wrong. Microsoft is trying to make an example out of Munich in all sorts of nefarious ways. We need to defend Munich from this malicious assault by the convicted monopolist and corrupt enterprise that’s acting as though it fights for its very survival (while indeed laying off tens of thousands of employees). Read more

Shortlist of open source software used at NASA lab

Yes! We use a lot of open source. The short list includes Python, GitHub, Processing, VLC, jQuery, D3.js, Blender, VRUI, ImageJ, VMD, ParaView, MeshLab, VNC, ImageMagick, SWIG, Emacs, and many more. We like using open source because it gives us more flexibility because of licensing and allows us the opportunity to contribute back to the community using our expertise. Our favorite open source project that we work on is OpenMDAO. This project is run out of another Division at our Center. Our team provides some programming support. OpenMDAO is an open source Multidisciplinary Design Analysis and Optimization (MDAO) framework, written in Python. You can use it to develop an integrated analysis and design environment for your engineering challenges. Read more

GSoC: Thumping the Malaria and voyaging in cosmos with KStars

Let's talk about my project now. KStars is desktop planetarium application under KDE Education Projects. I developed QML based cool interface to enable users to browse through image database of community of astrophotographers (i.e. astrobin.com) which contains more than 1,20,000 (number is increasing everyday) real time and very high resolution images along with various information related to them (i.e. Date on which image was captured, Bortle Dark-Sky Scale, RA Centre, DEC Centre, Telescope or Camera used, Description added by astrophotographer etc). I am sure that this browser will enthrall school children by showing them real time images of stars and galaxies located at hundreds of light year far from earth. Read more

Meet Cornelius Schumacher - Akademy Keynote Speaker

At Akademy 2014, outgoing KDE e.V. Board President Cornelius Schumacher will give the community keynote. He has attended every Akademy and has been amazed and inspired at every one of them. If you want more of what KDE can bring to your life, Cornelius's talk is the perfect elixir. Here are glimpses of Cornelius that most of us have never seen. They give a sense of what has made him a successful leader of KDE for several years. Read more