kernel IO schedulers

[Net Llama!]

On 12/31/2004 06:01 PM, Kurt Wall wrote:
> On Thu, Dec 30, 2004 at 06:58:34AM -0800, Net Llama! took 31 lines to write:
> 
>>I could be wrong, but I think that in 2.6.10 there's a choice of several 
>>different schedulers in the kernel:
>>
>># IO Schedulers
>>#
>>CONFIG_IOSCHED_NOOP=y
>>CONFIG_IOSCHED_AS=y
>>CONFIG_IOSCHED_DEADLINE=y
>>CONFIG_IOSCHED_CFQ=y
>>
>>What I'm wondering is what happens if you chose Y for all of them (as 
>>above)?
> 
> 
> Did you modify the scheduler with a command line argument, such as
> "eleveator=deadline"? You can replace "deadline" with "as" or "noop".
> There are also some tunables, but it eludes me right now where I read
> about them.

No, i did not.  However i rebuilt 2.6.10 with only CONFIG_IOSCHED_AS=y 
and confirmed in dmesg:
elevator: using anticipatory as default io scheduler

yet performance still sucketh.

>>The reason I'm asking is that I did choose Y for all of them, and now in 
>>2.6.10 (but not in earlier kernels) i'm getting some horrific 
>>performance in X (XFCE specifically).  Scrolling in windows is sluggish, 
>>sometimes even typing gets lagged.  I'm starting to think that I was 
>>supposed to choose just one of the schedulers, but I'd like some input.
> 
> 
> I have the same config (but on 2.6.9) and haven't noticed any grievous
> performance issues.

i guess i could try the deadline.

i guess this is what i get for jumping from 2.6.7 to 2.6.10 just for 
gits and shiggles.  *sigh*


-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
L. Friedman                       	       netllama at linux-sxs.org
Linux Step-by-step & TyGeMo: 		    http://netllama.ipfox.com

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