Re: Xen 4.3 development update

[George Dunlap <george.dunlap@eu.citrix.com>]

On 03/04/13 09:37, Christoph Egger wrote:
> On 02.04.13 19:06, Suravee Suthikulpanit wrote:
>> On 4/2/2013 11:34 AM, Tim Deegan wrote:
>>> At 16:42 +0100 on 02 Apr (1364920927), Jan Beulich wrote:
>>>>>>> On 02.04.13 at 16:07, George Dunlap <George.Dunlap@eu.citrix.com>
>>>>>>> wrote:
>>>>> * AMD NPT performance regression after c/s 24770:7f79475d3de7
>>>>>     owner: ?
>>>>>     Reference: http://marc.info/?l=xen-devel&m=135075376805215
>>>> This is supposedly fixed with the RTC changes Tim committed the
>>>> other day. Suravee, is that correct?
>>> This is a separate problem.  IIRC the AMD XP perf issue is caused by the
>>> emulation of LAPIC TPR accesses slowing down with Andres's p2m locking
>>> patches.  XP doesn't have 'lazy IRQL' or support for CR8, so it takes a
>>> _lot_ of vmexits for IRQL reads and writes.
>> Is there any tools or good ways to count the number of VMexit in Xen?
> xentrace -e 0x8f000 > xentrace.out
> [Hit ^C to abort]
> xentrace_format formats < xentrace.out > xentrace.dump
>
> You need to manually install 'formats' from tools/xentrace/formats
> to a proper place.

Even better is to use xenalyze "summary" mode:

http://xenbits.xen.org/ext/xenalyze

Build, then run:

xenalyze --svm-mode -s [trace file] > summary

  -George