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xen-devel
[Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL
 
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To:  | 
Dan Magenheimer <dan.magenheimer@xxxxxxxxxx>,	"Zhang, Xiantao" <xiantao.zhang@xxxxxxxxx>,	Ian Pratt <Ian.Pratt@xxxxxxxxxxxxx>,	"Xen-Devel (E-mail)" <xen-devel@xxxxxxxxxxxxxxxxxxx> | 
 
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Subject:  | 
[Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL | 
 
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From:  | 
Keir Fraser <keir.fraser@xxxxxxxxxxxxx> | 
 
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Date:  | 
Tue, 28 Jul 2009 16:00:14 +0100 | 
 
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Cc:  | 
"Dong, Eddie" <eddie.dong@xxxxxxxxx>, John Levon <levon@xxxxxxxxxxxxxxxxx> | 
 
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Tue, 28 Jul 2009 08:01:48 -0700 | 
 
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TSC scaling and softtsc reprise, and PROPOSAL | 
 
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On 28/07/2009 15:45, "Dan Magenheimer" <dan.magenheimer@xxxxxxxxxx> wrote:
> I am proposing that the virtual TSC be the default.
> We should provide a per-VM option and a Xen boot
> option to allow VMs to NOT trap rdtsc, but this
> should have a warning that it is not recommended
> and may result in data corruption in some apps.
This I can agree with. The softtsc boot option is just lazy. This should
properly be a per-VM option, for both HVM and PV guests. For example
tsc_freq=x sets virtual TSC of x MHz. And not specifying tsc_freq gets you
current behaviour (pass through host TSC where possible). That I could quite
happily live with, although I'm not planning to implement it myself.
 -- Keir
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- [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL, (continued)
 
- [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Dan Magenheimer
 - [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL, Keir Fraser
 - [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Dan Magenheimer
 - [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL, Keir Fraser
 - [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Dan Magenheimer
 - [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL, Keir Fraser
 
- [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Zhang, Xiantao
 - [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Dan Magenheimer
 - [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL,
Keir Fraser <=
 - [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Dan Magenheimer
 - [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL, Keir Fraser
 - [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Dan Magenheimer
 - [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL, Keir Fraser
 - [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Dan Magenheimer
 
- [Xen-devel] Re: TSC scaling and softtsc reprise, and PROPOSAL, Keir Fraser
 
- [Xen-devel] RE: TSC scaling and softtsc reprise, and PROPOSAL, Zhang, Xiantao
 
 
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