RE: [Xen-users] Xen scheduler setup

["Petersson, Mats" <Mats.Petersson@xxxxxxx>]

> -----Original Message-----
> From: xen-users-bounces@xxxxxxxxxxxxxxxxxxx 
> [mailto:xen-users-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of 
> Ashish Gupta
> Sent: 17 May 2007 23:05
> To: trilok nuwal
> Cc: Xen-users@xxxxxxxxxxxxxxxxxxx
> Subject: Re: [Xen-users] Xen scheduler setup
> 
> Also, you said "As from xen documantion, boot time 
> sched=credit or sedf is used to set the scheduler for the xen hosts."
> Boot time here refers to boot time of dom0 or boot time of 
> the guests ?

Boot time of the entire system (which means HyperVisor + Dom0). The
Scheduler isn't per domain, but per system, so it's set up and
initialized when the system boots (it is for example responsible for
running Dom0!)

--
Mats
> 
> thanks,
> Ashish
> 
> 
> 
> On 5/17/07, Ashish Gupta <ashishgup@xxxxxxxxx> wrote:
> 
>       Thanks Trilok for the clarification !
>       
>       On running some of your commands I get the following 
> output. Does this seem to indicate I am running the credit 
> scheduler ? xm dmesg doesn't tell me.
>       
>       I get the following output:
>       # xm sched-sedf
>       Name                              ID Period(ms) 
> Slice(ms) Lat(ms) Extra Weight
>       Domain-0                          -1      -0.0      
> -0.0    -0.0     -1     -1
>       domain1                           -1      -0.0      
> -0.0    -0.0     -1     -1
>       domain2                           -1      -0.0      
> -0.0    -0.0     -1     -1
>       [root@virtuoso-32 sys]# 
>       
>       # xm sched-credit
>       Error: No domain given.
>       Usage: xm sched-credit -d <Domain> [-w[=WEIGHT]|-c[=CAP]]
>       
>       Get/set credit scheduler parameters.
>         -d DOMAIN, --domain=DOMAIN     Domain to modify       
>                     
>         -w WEIGHT, --weight=WEIGHT     Weight (int)           
>                     
>         -c CAP, --cap=CAP              Cap (int)              
>                     
>       
>       # xm sched-credit -d 0
>       {'cap': 0, 'weight': 256}
>       
>       
>       
>       
>       On 5/17/07, trilok nuwal <tc.nuwal@xxxxxxxxx > wrote:
> 
> 
>               I havent tried this, but there are two sheduler 
> credit and sedf scheduler for xen host and this would be 
> common for all the domains. As from xen documantion, boot 
> time sched=credit or sedf is used to set the scheduler for 
> the xen hosts.
>               
>               For this there are two commands to set and get 
> the parameters of the scheduler for individual domin 
> depednding on the scheduler. Scheduler cant be differnet for 
> the different domains.
>               
>               #xm  sched-credit
>               #xm  sched-sedf  
>               
>               sched-credit         Get/set credit scheduler 
> parameters.
>                sched-sedf           Get/set EDF parameters.
>               
>               # xm sched-credit
>               Name                              ID Weight Cap
>               Domain-0                           0    256    0
>               os218                              7    256    0
>               # xm sched-sedf
>               Error: Xen is running with the credit scheduler
>               # xm sched-sedf --help
>               Usage: xm sched-sedf <Domain> [options]
>               
>               Get/set EDF parameters.
>                 -p [MS], --period[=MS]         Relative deadline(ms)
>                 -s [MS], --slice[=MS]          Worst-case 
> execution time(ms). (slice <
>                                                period)
>                 -l [MS], --latency[=MS]        Scaled period 
> (ms) when domain performs
>                                                heavy I/O
>                 -e [FLAG], --extra[=FLAG]      Flag (0 or 1) 
> controls if domain can run
>                                                in extra time.
>                 -w [FLOAT], --weight[=FLOAT]   CPU 
> Period/slice (do not set with
>                                                --period/--slice)
>               
>               # xm sched-credit --help
>               Usage: xm sched-credit [-d <Domain> 
> [-w[=WEIGHT]|-c[=CAP]]]
>               
>               Get/set credit scheduler parameters.
>                 -d DOMAIN, --domain=DOMAIN     Domain to modify
>                 -w WEIGHT, --weight=WEIGHT     Weight (int)
>                 -c CAP, --cap=CAP              Cap (int)
>               
>               
>               I dont think bvt scheduler is available in 
> latest xen 3.0 ( Not sure ).
>               Hope this will be worthful to you.
>               
>               Thanks,
>               -Trilok 
>               
>               
>               On 5/17/07, Ashish Gupta < ashishgup@xxxxxxxxx 
> <mailto:ashishgup@xxxxxxxxx> > wrote:
> 
>                       Hi,
>                       
>                       I have been trying to setup Xen 
> scheduling but have some questions:
>                       1. When do we exactly specify the 
> scheduler to use ? At dom0 boot time (i.e. when the host 
> boots) or when the domU is created with xm ? 
>                       
>                       2. Can we change the scheduler when a 
> domU is already running ? 
>                       
>                       3. Can we change the existing scheduler 
> parameters at runtime for domU or dom0 ?
>                       
>                       4. How do we figure out which scheduler 
> is currently being used ?
>                       
>                       The answers are probably 
> straightforward but I haven't found a tutorial or a guide 
> that explains these points, esp 2,3, or 4.
>                       
>                       I am trying to experiment with the bvt 
> scheduler and tried passing sched=bvt at xm create time. But 
> I can't figure out if its actually being used or how to 
> change its parameters.
>                       Any help is greatly appreciated.
>                       
>                       thanks,
>                       Ashish
>                       
>                       -- 
>                       http://www.cs.northwestern.edu/~agupta 
> <http://www.cs.northwestern.edu/%7Eagupta>  
>                       
>                       _______________________________________________
>                       Xen-users mailing list
>                       Xen-users@xxxxxxxxxxxxxxxxxxx 
>                       http://lists.xensource.com/xen-users
>                       
> 
> 
> 
> 
> 
>       -- 
>       http://www.cs.northwestern.edu/~agupta 
> <http://www.cs.northwestern.edu/%7Eagupta>  
> 
> 
> 
> 
> -- 
> http://www.cs.northwestern.edu/~agupta 
> 



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