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I am evaluating the rteval test to see whether it is a useful tool for us.

In the current form, it is not packaged, and depends upon a library which is not packaged. These instructions only work for Natty and later.

In order to install and run it on Ubuntu (Oneiric), these are the steps:

1. Install the required packages:
   • sudo apt-get install python-ethtool python-libxslt1 python-dmidecode rt-tests python-dev git
2. Install python-schedutils from source:

   • wget http://people.canonical.com/~sconklin/rteval/python-schedutils-0.3.tar.bz2

   • tar jxvf python-schedutils-0.3.tar.bz2
   • cd python-schedutils-0.3
   • sudo python setup.py install
   • cd ..
3. Fetch and install rteval:
   • git clone git://github.com/sconklin/rteval.git
   • cd rteval/loadsource

   • wget http://www.kernel.org/pub/linux/kernel/v3.0/linux-3.1.1.tar.bz2

   • cd ..
   • sudo make install
4. Run rteval from terminal for generic kernel (for 6 minutes duration):

   • sudo python /usr/local/lib/python2.7/dist-packages/rteval/rteval.py -d360.0 > rteval-$USER-generic-normal.txt

   • this dumps the test results into a text file in your /home directory
5. Run rteval from console (to check if cgroups affects test) for generic kernel (for 6 minutes duration):
   • clt-alt-F1 (to get to console)
   • log in

   • sudo python /usr/local/lib/python2.7/dist-packages/rteval/rteval.py -d360.0 > rteval-$USER-generic-console.txt

   • this dumps the test results into a text file in your /home directory
6. Install -lowlatency kernel
   • install abogani's ppa from termainal
     • sudo add-apt-respository ppa:abogani/lowlatency
     • sudo apt-get update
     • sudo apt-get install linux-lowlatency
7. Reboot
8. Run rteval from terminal for lowlatency kernel (for 6 minutes duration):

   • sudo python /usr/local/lib/python2.7/dist-packages/rteval/rteval.py -d360.0 > rteval-$USER-lowlatency-normal.txt

   • this dumps the test results into a text file in your /home directory
9. Run rteval from console (to check if cgroups affects test) for lowlatency kernel (for 6 minutes duration):
   • clt-alt-F1 (to get to console)
   • log in

   • sudo python /usr/local/lib/python2.7/dist-packages/rteval/rteval.py -d360.0 > rteval-$USER-lowlatency-console.txt

   • this dumps the test results into a text file in your /home directory

10. email results to scottalavender@gmail.com, be sure to put 'rteval' in the subject line of the email.

Which low latency kernel are we testing?

The -lowlatecny kernel is available on kernel.ubuntu.com/git (that is http://kernel.ubuntu.com/git?p=abogani/ubuntu-precise-lowlatency.git;a=summary).

The -lowlatency kernel uses a different configuration: http://kernel.ubuntu.com/git?p=abogani/ubuntu-precise-lowlatency.git;a=blob;f=debian.lowlatency/config/config.flavour.lowlatency;h=491ecd9bba7b7ceab095632f84286148c6fbd4a3;hb=HEAD

And a little patch to force kernel to put IRQ handlers in threads: http://kernel.ubuntu.com/git?p=abogani/ubuntu-precise-lowlatency.git;a=blob;f=debian.lowlatency/patches/made-kernel-irq-threaded-by-default.patch;h=390c876f853e8fbf4d692a1bd16aa3cfc290adfd;hb=HEAD