Re: [Xen-devel] [PATCH] xen: allocate page for shared info page from low memory

2017-07-24 Thread Boris Ostrovsky
On 07/23/2017 04:25 PM, Boris Ostrovsky wrote: On 06/14/2017 01:11 PM, Juergen Gross wrote: On 14/06/17 18:58, Boris Ostrovsky wrote: On 06/12/2017 07:53 AM, Juergen Gross wrote: In a HVM guest the kernel allocates the page for mapping the shared info structure via extend_brk() today. This

Re: [Xen-devel] [PATCH] xen: allocate page for shared info page from low memory

2017-07-23 Thread Boris Ostrovsky
On 06/14/2017 01:11 PM, Juergen Gross wrote: On 14/06/17 18:58, Boris Ostrovsky wrote: On 06/12/2017 07:53 AM, Juergen Gross wrote: In a HVM guest the kernel allocates the page for mapping the shared info structure via extend_brk() today. This will lead to a drop of performance as the underly

Re: [Xen-devel] [PATCH] xen: allocate page for shared info page from low memory

2017-06-14 Thread Boris Ostrovsky
On 06/14/2017 01:11 PM, Juergen Gross wrote: > On 14/06/17 18:58, Boris Ostrovsky wrote: >> On 06/12/2017 07:53 AM, Juergen Gross wrote: >>> In a HVM guest the kernel allocates the page for mapping the shared >>> info structure via extend_brk() today. This will lead to a drop of >>> performance as

Re: [Xen-devel] [PATCH] xen: allocate page for shared info page from low memory

2017-06-14 Thread Juergen Gross
On 14/06/17 18:58, Boris Ostrovsky wrote: > On 06/12/2017 07:53 AM, Juergen Gross wrote: >> In a HVM guest the kernel allocates the page for mapping the shared >> info structure via extend_brk() today. This will lead to a drop of >> performance as the underlying EPT entry will have to be split up i

Re: [Xen-devel] [PATCH] xen: allocate page for shared info page from low memory

2017-06-14 Thread Boris Ostrovsky
On 06/12/2017 07:53 AM, Juergen Gross wrote: > In a HVM guest the kernel allocates the page for mapping the shared > info structure via extend_brk() today. This will lead to a drop of > performance as the underlying EPT entry will have to be split up into > 4kB entries as the single shared info pag

[Xen-devel] [PATCH] xen: allocate page for shared info page from low memory

2017-06-12 Thread Juergen Gross
In a HVM guest the kernel allocates the page for mapping the shared info structure via extend_brk() today. This will lead to a drop of performance as the underlying EPT entry will have to be split up into 4kB entries as the single shared info page is located in hypervisor memory. The issue has bee