Talk:Linux-ck

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BFQ Scheduler auto loading

Inspired by a forumpost i recommend to ad the following text and script to the Wiki at the end of section 2.2.5:

When using more than one kernel at the same system, you can use the following script in /etc/rc.local This will automitically load the BFQ Scheduler only when kernel26-ck is loaded. The BFQ status will be written to a logfile.

#Enable BFQ for precompiled kernel26-ck from the unofficial repository
TID=$(date +%c)
KERN=$(uname -r | cut -d"-" -f2)
if [ "$KERN" == 'ck' ]; then
modprobe bfq-iosched
echo bfq > /sys/block/sda/queue/scheduler
echo "$TID $(uname -r) with $KERN patch so started bfq for sda" >> /var/log/bfq.log
else
echo "$TID $(uname -r) no bfq loaded" >> /var/log/bfq.log
fi
Thanks for the suggestion. I modified the linux-ck package to actually compile in the BFQ (just not enabled by default). Once CK and Paolo get release their respective patches for 3.0.1, I'll update the repo and the wiki page. Thanks for the re-direct btw! Graysky 17:12, 8 August 2011 (EDT)
It seems like BFQ was not compiled into linux-ck-core2 3.0.1-3 ("zcat /proc/config.gz | grep BFQ" shows nothing, and I'm running the -ck kernel).Jimreynold2nd 14:44, 15 August 2011 (EDT)
Right, that's because BFQ for 3.0 does not yet exist. Paolo hasn't released the code for the 3.0 series :) I will update as soon as he does. Graysky 04:32, 16 August 2011 (EDT)

Enabling BFQ selectively section

This section should be updated: you say to put the "echo bfq" command in rc.local...there is no more support for it, and there is: 1)the systemd-way -> tmpfiles 2)the udev-rule way.

May be you should report both, or choose what do you think is the best, i trust you!

Thanks for your time (i preferred to open discussion rather than change it myself, did i the right thing?)

New section 2.2.3: rerun grub-mkconfig

After the installation subsection, I would suggest adding a new subsection to remind folks to rerun grub-mkconfig (or the appropriate boot reconfig command for their bootloader) and reboot, so they will be able to see the new kernel and CPU scheduler in action right away. They will have to do this whether or not they want to enable bfq, as I just found out from a kind soul on the Arch Linux Google+ group.

This step may be obvious to old hands, but as an Arch newb whose system was frequently maxing out, I needed to try BFS and bfq as soon as possible. I'm still getting used to generating a grub config file myself instead of having the installer do it for me...!