WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] More on sedf scheduler

To: xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] More on sedf scheduler
From: Stephan Diestelhorst <sd386@xxxxxxxxxxxx>
Date: Thu, 14 Jul 2005 20:09:05 +0100
Delivery-date: Thu, 14 Jul 2005 19:07:55 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <42D6ABE6.1030502@xxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <1121191749.3860.4.camel@xxxxxxxxxxxxxxxxxxxxxxx> <200507141725.00390.sd386@xxxxxxxxxxxx> <42D696AC.207@xxxxxx> <200507141839.58983.sd386@xxxxxxxxxxxx> <42D6ABE6.1030502@xxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla Thunderbird 1.0 (Windows/20041206)
>Stephan Diestelhorst wrote:

>
>> Thanks,
>>  what is your dom0 tight loop doing? Heavy I/O?
>> It looks like dom0 does a lot of I/O, which immediatelly unblocks and
>> then gets a higher priority in the L1 extraq, without anybounds on
>> executiontime, i.e. slice length. Can you confirm this?
>>
>> Stephan
>>  
>>
>
> The loop was just while(1); There was also a python script running
> that was reading from xentrace. So no heavy i/o, at least no
> disk/network i/o. But that doesn't matter anyway. Here is another dump
> where dom0 is doing absolutely nothing besides while (1); And dom1 is
> completely comatose during this time.
>
Thanks for the dump! It looks as something is seriously broken, as the
scheduler thinks that dom0 needs compensation for block loss... Strange!
I'll try to reproduce and fix the bug, probably tonight, but def. tomorrow!

Thanks,
  Stephan

>  
>
>
> (XEN) Scheduler: Simple EDF Scheduler (sedf)
> (XEN) NOW=0x0000004AC8DEB496
> (XEN) CPU[00] now=321199566451
> (XEN) RUNQ rq ff18cf80   n: ff18cf80, p: ff18cf80
> (XEN)
> (XEN) WAITQ rq ff18cf88   n: ffbf7e04, p: ff1bfe04
> (XEN)   0: 0.0 has=T p=20000000 sl=15000000 ddl=321220001780 w=0
> c=34111278898 sc=451020117 xtr(yes)=11730339611 ew=0 (34%)
> (XEN)   1: 1.0 has=F p=100000000 sl=0 ddl=321370002222 w=0
> c=20938650825 sc=131072 xtr(yes)=20938650825 ew=1 (100%)
> (XEN)
> (XEN) EXTRAQ (penalty) rq ff18cf90   n: ffbf7e0c, p: ffbf7e0c
> (XEN)   0: 0.0 has=T p=20000000 sl=15000000 ddl=321220001780 w=0
> c=34111278898 sc=451020117 xtr(yes)=11730339611 ew=0 (34%)
> (XEN)
> (XEN) EXTRAQ (utilization) rq ff18cf98   n: ff1bfe14, p: ffbf7e14
> (XEN)   0: 1.0 has=F p=100000000 sl=0 ddl=321370002222 w=0
> c=20938650825 sc=131072 xtr(yes)=20938650825 ew=1 (100%)
> (XEN)   1: 0.0 has=T p=20000000 sl=15000000 ddl=321220001780 w=0
> c=34111278898 sc=451020117 xtr(yes)=11730339611 ew=0 (34%)
> (XEN)
> (XEN) not on Q
>
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel




_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel