Arch Linux

edward.taylor89

Member

From: UK

Registered: 2010-10-21

Posts: 34

BFQ Hierarchal scheduling support..

I can't seem to find any info regarding this over the internet..

It is an option for the BFQ scheduler, available in the general config of kernel26-ck.

Could someone kindly explain what this is for me please?

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'The perfect blossom is a rare thing. You could spend your life looking for one, and it would not be a wasted life.'

harryNID

Member

From: P3X-1971

Registered: 2009-06-12

Posts: 117

Re: BFQ Hierarchal scheduling support..

I can't seem to find any info regarding this over the internet..

It is an option for the BFQ scheduler, available in the general config of kernel26-ck.

Could someone kindly explain what this is for me please?

Yes, it's optional.

Your question is kinda vague so I will try to hit some points and maybe your question will be answered.

First, if you don't know what BFQ is read here:
BFQ and related stuff on disk scheduling

Second, to enable it in kernel26-ck use a text editor and change these parameters at the top of the PKGBUILD

###########################################################################################################
_BFQ_patches="n"    # add BFQ patches
_makemenucfg="n"    # menuconfig option
_streamline_="n"    # run Steven Rostedt's streamline_config.pl script - see notes below!
_use_current="n"    # use the current kernel's .config file - see notes below!
###########################################################################################################
#                                        More Details and References
###########################################################################################################
## Note all kernels get the ck patch set - there is no option to enable/disable it!
## BFQ
 # read, http://algo.ing.unimo.it/people/paolo/disk_sched/
## MAKEMENUCONFIG OPTION
 # Allow you to select additional kernel options prior to a build via a menuconfig.
## STREAMLINE_CONFIG OPTION
 # Similar to a make localmodconfig but this actually works!
 # WARNING - make CERTAIN that all modules are modprobed BEFORE you begin making the pkg!
 # read, https://bbs.archlinux.org/viewtopic.php?pid=830221#p830221
 # to keep track of which modules are needed for your specific system/hardware, give my module_db script.
 # a try: http://aur.archlinux.org/packages.php?ID=41689
 # Not that if you use my script, this PKGBUILD will auto run the reload_data base for you to probe
 # all the modules you have logged!
## USE CURRENT KERNEL'S .CONFIG
 # Enabling this option will use the .config of the RUNNING kernel rather than the ARCH defaults.
 # Useful when the package gets updated and you already went through the trouble of customizing your
 # config options.  NOT recommended when a new kernel is released, but again, convenient for package bumps.
###########################################################################################################

Just change the "n" to a "y" under "_BFQ_patches=" to enable BFQ and have it set to your default disk scheduler. If you prefer CFQ then just leave it set to "n".

Hopefully that cleared it up for you.

Cheers!

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In solving a problem of this sort, the grand thing is to be able to reason backward. That is a very useful accomplishment, and a very easy one, but people do not practice it much. In the everyday affairs of life it is more useful to reason forward, and so the other comes to be neglected. There are fifty who can reason synthetically for one who can reason analytically.  --Sherlock Holmes