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-users

Re: [Xen-users] limit of domUs ?

To: "Petersson, Mats" <Mats.Petersson@xxxxxxx>
Subject: Re: [Xen-users] limit of domUs ?
From: Yura Pismerov <y.pismerov@xxxxxxxxxxxxx>
Date: Mon, 05 Jun 2006 11:32:24 -0400
Cc: xen-users@xxxxxxxxxxxxxxxxxxx
Delivery-date: Mon, 05 Jun 2006 08:33:10 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <907625E08839C4409CE5768403633E0BA7FCE8@xxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <907625E08839C4409CE5768403633E0BA7FCE8@xxxxxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mail/News 1.5 (X11/20060228)
Petersson, Mats wrote:
> What amount of memory have you given to Dom0? If Dom0 starts out with a
> lot of memory, it's quite likely that it's not going to shrink to
> "nothing" when more memory is needed by DomU's. 
>   

I tried 256 and 512 - it does not make any difference.
Besides, there is a few gigs of RAM available (according to xentop) by
the time I get the error.

> As far as I'm aware, the number of domains should be limited only by the
> available memory. 
>
> However, there's also the Xen internal heap. It's default size is 12MB,
> and it's not adjustable at run-time or by boot parameter[1]. I guess you
> could change the source [.../xen/include/asm-x86/config.h:
> XENHEAP_DEFAULT_MB - which is defined as DIRECTMAP_MBYTES, which is 12
> in my version of the source code (fairly recent). 
>
> [1] If you're running x86_64 or IA64 it IS adjustable, but not in 32-bit
> kernel version. Don't ask me why that is... But Keir stated more than
> once that they are not going to change the size of the heap, so I guess
> it's that size for a good reason... If you're running x86_64/IA64, the
> parameter to the kernel is xenheap_megabytes, and it takes an integer
> number. 
>   

I run x86_64, so I will try to adjust that parameter.
Thanks.


> --
> Mats
>
>   
>> -----Original Message-----
>> From: xen-users-bounces@xxxxxxxxxxxxxxxxxxx 
>> [mailto:xen-users-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of 
>> Yura Pismerov
>> Sent: 05 June 2006 15:29
>> To: 'xen-users@xxxxxxxxxxxxxxxxxxx'
>> Subject: [Xen-users] limit of domUs ?
>>
>>
>> What is the max number of domains one can create in Xen 3.0.2 ?
>> For some reason, no matter what amount of RAM I allocate for 
>> the domU's I can only create about 100 of them.
>> After that I receive  "Error: (12, 'Cannot allocate 
>> memory')", even though there is still plenty of free RAM available.
>> Where should I look ?
>>
>>
>>
>> _______________________________________________
>> Xen-users mailing list
>> Xen-users@xxxxxxxxxxxxxxxxxxx
>> http://lists.xensource.com/xen-users
>>
>>
>>     
>
>   


-- 
Yuri Pismerov, System Administrator
Armor Technologies (Canada) Inc.

P: 905 305 1946 (x.3519)
http://www.armorware.net

Privacy Protection Guaranteed!




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

<Prev in Thread] Current Thread [Next in Thread>