Hi Connie,

I investigated a slow behaviour of guest VM (paravirtualized SL 48) in my 
host computer (host OS SL53). No serious clue was found still. However I 
paid attention in my routine checking of all parametrs for the flag 'vmx' 
on host OS and the difference with different versions of kernels.

I am not expert in kernels and I asked who may be already has 
experience with such the case.

Actually I do not care if the kernel has small problem to show all CPU 
flags.

But if the kernel somehow ignores such flag (or reset it!) - it is more 
serious.

Thanks for attention,

Andrey


On Wed, 16 Jun 2010, Connie Sieh wrote:

> Date: Wed, 16 Jun 2010 14:09:48 -0500 (CDT)
> From: Connie Sieh <[log in to unmask]>
> To: Andrey Y. Shevel <[log in to unmask]>
> Cc: [log in to unmask]
> Subject: Re: Q on the CPU flag 'vmx'
> 
> Why do you care if it says "vmx" or not?  Does it not work in one of the 
> cases?
>
> -Connie Sieh
> On Wed, 16 Jun 2010, Andrey Y. Shevel wrote:
>
>>  Hi Andrew,
>>
>>  I would pay attention that in both described cases XEN kernels were used.
>>
>>  Andrey
>> 
>>
>>  On Wed, 16 Jun 2010, Dr Andrew C Aitchison wrote:
>> 
>> >  Date: Wed, 16 Jun 2010 10:58:44 +0100 (BST)
>> >  From: Dr Andrew C Aitchison <[log in to unmask]>
>> >  To: Andrey Y. Shevel <[log in to unmask]>
>> >  Cc: [log in to unmask]
>> >  Subject: Re: Q on the CPU flag 'vmx'
>> > 
>> >  On Wed, 16 Jun 2010, Andrey Y. Shevel wrote:
>> > 
>> > >   Hello everybody,
>> > > 
>> > >   I just discovered in my CPU
>> > > 
>> > >   model name      : Intel(R) Xeon(R) CPU           E5430  @ 2.66GHz
>> > > 
>> > >   under
>> > > 
>> > >   [root@pcfarm-new ~]# uname -a
>> > >   Linux pcfarm-new.pnpi.spb.ru 2.6.18-194.3.1.el5xen #1 SMP Fri May 7
>> > >   02:05:32 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux
>> > > 
>> > >   that there is no flag 'vmx'
>> > > 
>> > >   [root@pcfarm-new ~]# grep vmx /proc/cpuinfo; echo $?
>> > >   1
>> > > 
>> > >   At the same time when I boot another kernel 
>> > >   'xen.gz-2.6.18-128.1.1.el5'
>> > >   the flag 'vmx' is in place
>> > 
>> >  Hmm. The flags are indeed different with xen and non-xen kernels.
>> > 
>> >  I guess this is because with a xen kernel you are looking at the 
>> >  capabiities
>> >  of the *virtual* CPU, rather than the bare metal processor ?
>> > 
>> > 
>> 
>> 
>

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