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[Bug 631871] Re: default I/O scheduler should be change from CFQ to deadline

 

@Charlie, DLHDavidLH,

The correct place to discuss this is on the ubuntu kernel team mailing
list: kernel-team@xxxxxxxxxxxxxxxx

-- 
default I/O scheduler  should be change from CFQ to deadline
https://bugs.launchpad.net/bugs/631871
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Status in Ubuntu: Won't Fix

Bug description:
i think that the default I/O scheduler

 should be change from   CFQ   to   deadline

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i have test CFQ and deadline I/O scheduler

on a DELL Latitude 120L with 1GB of RAM and 40GB hard drive

with EXT4 filesystem and GPT with both I/O schedulers

and Found that deadline I/O scheduler is the fastest

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also tested
 EXT3 with MBR and deadline I/O scheduler
 EXT3 with GPT and deadline I/O scheduler

 EXT4 with MBR and deadline I/O scheduler
 EXT4 with GPT and deadline I/O scheduler

 EXT4 with MBR and Noop I/O scheduler
 EXT4 with GPT and Noop I/O scheduler

-- all are faster with 
deadline  I/O scheduler -OR- Noop I/O scheduler

ubuntu versions tested - Ubuntu 9.04, Ubuntu 10.04  (LTS),  Xubuntu 10.04

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also test both I/O schedulers on two other computers (total of 3 computers)

the deadline I/O scheduler preformed faster then CFQ scheduler

Noop  I/O scheduler preformed best ( faster then deadline )

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also went deadline I/O scheduler is put in Grub ( etc/default/grub OR grub.cfg )
the boot speed is increased and desktop speed

OR went deadline I/O scheduler is put in rc.local ( etc/rc.local )
the desktop speed is increased only

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http://en.wikipedia.org/wiki/Deadline_scheduler
http://en.wikipedia.org/wiki/Noop_scheduler
http://en.wikipedia.org/wiki/GUID_Partition_Table
http://en.wikipedia.org/wiki/Ext4
http://itezer.com/blog/ubuntu-linux/125-Four_Tweaks_for_Using_Ubuntu_with_SSD.html

http://en.wikipedia.org/wiki/CFQ