linux-kernel - Re: [PATCH v8 08/25] x86/resctrl: Introduce interface to display number of monitoring counters

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Message-ID: <0ee2e67d-c1dd-489e-beef-1f255c5629d6@amd.com>
Date: Mon, 14 Oct 2024 12:20:29 -0500
From: "Moger, Babu" <babu.moger@....com>
To: Reinette Chatre <reinette.chatre@...el.com>,
 Tony Luck <tony.luck@...el.com>
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Subject: Re: [PATCH v8 08/25] x86/resctrl: Introduce interface to display
 number of monitoring counters



On 10/14/24 11:46,  wrote:
> Hi Tony,
> 
> On 10/11/24 2:36 PM, Tony Luck wrote:
>> On Fri, Oct 11, 2024 at 03:49:48PM -0500, Moger, Babu wrote:
>>
>> I.e. the user who chose this simply gave up being able to
>> read total bandwidth on domain 1, but didn't get an extra
>> counter in exchange for this sacrifice. That doesn't seem
>> like a good deal.
> 
> As Babu mentioned earlier, this seems equivalent to the existing
> CLOSid management. For example, if a user assigns only CPUs
> from one domain to a resource group, it does not free up the
> CLOSID to create a new resource group dedicated to other domain(s).
> 

Thanks for the confirmation here.

I was wondering if this works differently on Intel. I was trying to figure
out on 2 socket intel system if we can create two separate resctrl groups
sharing the same CLOSID (one group using CLOSID 1 on socket 0 and another
group CLOSID 1 socket 1). No. We cannot do that.

Even though hardware supports separate allocation for each domain, resctrl
design does not support that.
-- 
Thanks
Babu Moger