On 5-9-2015 18:53, Stephen wrote:
> On 9/1/2015 8:06 AM, Thomas de Groot wrote:
>> If my bottle of wine is considered 100% full, what would be 200%? Two
>> bottles of wine? :-)
>
> One full bottle and a lot of spillage. ;-)
>

That was my conclusion too...

[finishes mopping up the mess left on the table]

-- 
Thomas

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On 01/09/2015 02:24 PM, scott wrote:
> Yes, typically % is defined as % of some (obvious) maximum. Defining CPU
> load as a % of only 1 core being fully loaded seems a bit
> counter-intuitive. But so long as everyone is aware of this, and they
> know exactly how many cores are in the CPU then it shouldn't be a huge
> problem. If we didn't know there were 8 cores, 800% could mean anything.

The fun part is when you have 4 cores with hyperthreading, and a task 
manages to consume more than 800% CPU...

In other news, the Windows "Process Explorer" tool considers my computer 
to have 8 physical cores, when in fact it has 4 cores with 2x 
hyperthreading. Which means that maximum utilisation is reported as 50%...

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On 18-9-2015 19:23, Orchid Win7 v1 wrote:
> The fun part is when you have 4 cores with hyperthreading, and a task
> manages to consume more than 800% CPU...
>
> In other news, the Windows "Process Explorer" tool considers my computer
> to have 8 physical cores, when in fact it has 4 cores with 2x
> hyperthreading. Which means that maximum utilisation is reported as 50%...

Running the marathon with one body / two legs is hyperthreading without 
knowing it... ;-)

-- 
Thomas

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Am 19.09.2015 um 09:21 schrieb Thomas de Groot:
> On 18-9-2015 19:23, Orchid Win7 v1 wrote:
>> The fun part is when you have 4 cores with hyperthreading, and a task
>> manages to consume more than 800% CPU...
>>
>> In other news, the Windows "Process Explorer" tool considers my computer
>> to have 8 physical cores, when in fact it has 4 cores with 2x
>> hyperthreading. Which means that maximum utilisation is reported as
>> 50%...
> 
> Running the marathon with one body / two legs is hyperthreading without
> knowing it... ;-)

I /think/ that analogy limps a bit, as we'd say in German ;)

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On 20-9-2015 1:26, clipka wrote:
> Am 19.09.2015 um 09:21 schrieb Thomas de Groot:
>> On 18-9-2015 19:23, Orchid Win7 v1 wrote:
>>> The fun part is when you have 4 cores with hyperthreading, and a task
>>> manages to consume more than 800% CPU...
>>>
>>> In other news, the Windows "Process Explorer" tool considers my computer
>>> to have 8 physical cores, when in fact it has 4 cores with 2x
>>> hyperthreading. Which means that maximum utilisation is reported as
>>> 50%...
>>
>> Running the marathon with one body / two legs is hyperthreading without
>> knowing it... ;-)
>
> I /think/ that analogy limps a bit, as we'd say in German ;)
>

Of course, but I couldn't resist.

-- 
Thomas

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> In other news, the Windows "Process Explorer" tool considers my computer
> to have 8 physical cores, when in fact it has 4 cores with 2x
> hyperthreading. Which means that maximum utilisation is reported as 50%...

Ditto here, but all CPU-intensive apps I've got manage to get to a 
reported 100% CPU (POV, commerical simulation tools, multi-threaded C# 
apps, etc).

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On 21/09/2015 08:00 AM, scott wrote:
>> In other news, the Windows "Process Explorer" tool considers my computer
>> to have 8 physical cores, when in fact it has 4 cores with 2x
>> hyperthreading. Which means that maximum utilisation is reported as
>> 50%...
>
> Ditto here, but all CPU-intensive apps I've got manage to get to a
> reported 100% CPU (POV, commerical simulation tools, multi-threaded C#
> apps, etc).

Are you looking at the Windows Task Manager rather than the System 
Internals Process Explorer?

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>>> In other news, the Windows "Process Explorer" tool considers my computer
>>> to have 8 physical cores, when in fact it has 4 cores with 2x
>>> hyperthreading. Which means that maximum utilisation is reported as
>>> 50%...
>>
>> Ditto here, but all CPU-intensive apps I've got manage to get to a
>> reported 100% CPU (POV, commerical simulation tools, multi-threaded C#
>> apps, etc).
>
> Are you looking at the Windows Task Manager rather than the System
> Internals Process Explorer?

Both:

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On 22/09/2015 07:41 AM, scott wrote:
>>> Ditto here, but all CPU-intensive apps I've got manage to get to a
>>> reported 100% CPU (POV, commerical simulation tools, multi-threaded C#
>>> apps, etc).
>>
>> Are you looking at the Windows Task Manager rather than the System
>> Internals Process Explorer?
>
> Both:

Interesting. Perhaps you have a newer version of Process Explorer? Or 
maybe there's some setting somewhere to configure this that I haven't 
noticed...

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> Interesting. Perhaps you have a newer version of Process Explorer? Or
> maybe there's some setting somewhere to configure this that I haven't
> noticed...

v16.05 here, can't see any relevant setting.

If I tell POV to render with 6 threads I only get 50% usage, but with 12 
threads I get 100% usage.

However the elapsed times for the benchmark are:
6 threads  : 192s
12 threads : 136s

So 50% CPU is actually more like 70% CPU, but I guess it depends on the 
exact algorithm (how nicely it can hyperthread).

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