Messages in this thread | | | Date | Wed, 16 Sep 2009 09:31:04 -0400 | From | Konrad Rzeszutek Wilk <> | Subject | Re: [Xen-devel] [RFC][PATCH 0/10] Xen Hybrid extension support |
| |
On Wed, Sep 16, 2009 at 04:42:21PM +0800, Sheng Yang wrote: > Hi, Keir & Jeremy > > This patchset enabled Xen Hybrid extension support. > > As we know that PV guest have performance issue with x86_64 that guest kernel > and userspace resistent in the same ring, then the necessary TLB flushes when > switch between guest userspace and guest kernel cause overhead, and much more > syscall overhead is also introduced. The Hybrid Extension estimated these > overhead by putting guest kernel back in (non-root) ring0 then achieve the better > performance than PV guest.
What was the overhead? Is there a step-by-step list of operations you did to figure out the performance numbers?
I am asking this b/c at some point I would like to compare the pv-ops vs native and I am not entirely sure what is the best way to do this.
| |