linux-kernel - Re: [PATCH RFC 0/3] Add guest cpu

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <503BC298.3080306@redhat.com>
Date:	Mon, 27 Aug 2012 11:55:20 -0700
From:	Avi Kivity <avi@...hat.com>
To:	Michael Wolf <mjw@...ux.vnet.ibm.com>
CC:	linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
	peterz@...radead.org, mtosatti@...hat.com, glommer@...allels.com,
	mingo@...hat.com
Subject: Re: [PATCH RFC 0/3] Add guest cpu_entitlement reporting

On 08/23/2012 04:14 PM, Michael Wolf wrote:
> This is an RFC regarding the reporting of stealtime.  In the case of
> where you have a system that is running with partial processors such as
> KVM the user may see steal time being reported in accounting tools such
> as top or vmstat.  This can cause confusion for the end user.  To
> ease the confusion this patch set adds a sysctl interface to set the
> cpu entitlement.  This is the percentage of cpu that the guest system is
>  expected to receive.  As long as the steal time is within its expected
> range it will show up as 0 in /proc/stat.  The user will then see in the
> accounting tools that they are getting a full utilization of the cpu
> resources assigned to them.
>
> This patchset is changing the contents/output of /proc/stat and could affect 
> user tools.  However the default setting is that the cpu is entitled to 100% 
> so the code will act as before.  Also another field could be added to the 
> /proc/stat output and show the unaltered steal time. Since this additional 
> field could cause more confusion than it would clear up I have left it out 
> for now.
>                 

How would a guest know what its entitlement is?


-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/