[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH RFC V8 0/17] Paravirtualized ticket spinlocks



On 05/07/2012 06:52 PM, Avi Kivity wrote:
On 05/07/2012 04:20 PM, Raghavendra K T wrote:
On 05/07/2012 05:36 PM, Avi Kivity wrote:
On 05/07/2012 01:58 PM, Raghavendra K T wrote:
On 05/07/2012 02:02 PM, Avi Kivity wrote:
On 05/07/2012 11:29 AM, Ingo Molnar wrote:
This is looking pretty good and complete now - any objections
from anyone to trying this out in a separate x86 topic tree?

No objections, instead an

Acked-by: Avi Kivity<avi@xxxxxxxxxx>

[...]

(Less is better. Below is time elapsed in sec for x86_64_defconfig
(3+3 runs)).

           BASE                    BASE+patch            %improvement
           mean (sd)               mean (sd)
case 1x:     66.0566 (74.0304)      61.3233 (68.8299)     7.16552
case 2x:     1253.2 (1795.74)      131.606 (137.358)     89.4984
case 3x:     3431.04 (5297.26)      134.964 (149.861)     96.0664


You're calculating the improvement incorrectly.  In the last case, it's
not 96%, rather it's 2400% (25x).  Similarly the second case is about
900% faster.


You are right,
my %improvement was intended to be like
if
1) base takes 100 sec ==>  patch takes 93 sec
2) base takes 100 sec ==>  patch takes 11 sec
3) base takes 100 sec ==>  patch takes 4 sec

The above is more confusing (and incorrect!).

Better is what you told which boils to 10x and 25x improvement in case
2 and case 3. And IMO, this *really* gives the feeling of magnitude of
improvement with patches.

I ll change script to report that way :).


btw, this is on non-PLE hardware, right?  What are the numbers for PLE?

Sure.
I 'll get hold of a PLE mc  and come up with the numbers soon. but I
'll expect the improvement around 1-3% as it was in last version.


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.