Spectre and Meltdown impact on WinCC OA performances?

[adaneau]

Hi all,

Guess few of you are aware of the recent earthquake in IT world :ohmy: :

https://techcrunch.com/2018/01/03/kerne ... nd-device/


Does ETM already have an idea of the impact of this on WinCC OA? Intel is stating that their CPU will have performance loss between 5- 30% with the fix. How much will this impact WinCC OA?


If no answer yet, is there any benchmark planned when fix will be released by Intel / AMD?

Thanks


Alexandre

[mkoller]

My personal opinion to this is: does it (the possible security problem) affect you ?
As I see it, this is yet another finding which is mostly good for the media. They have something to write about and sell their stories.
They love headlines with "panic", "desaster", "catastrophy" in them - but: is it really for you ?
If you have secured your SCADA machines (non cloud of course!) in a way that nobody can install or run any arbitrary software, why should this problem matter at all ?

disclaimer: personal, non official ETM opinion

[adaneau]

Hi Martin,

Thanks for answer. The security part is actually not my concern as I see it mostly like as you said some media stuff.

I am more concerned by the announcement of Intel saying that all CPU will loss 5 to 30% performances depending of the tasks (eg: this will impact a lot compilation).

We made all our values changes estimations based on our Intel Xeon capabilities (before Intel fix), thus is suddenly a CPU able to handle 60000 VC /sec can only 40000, this is quite a problem for us on our big setups...

Anyway I guess it will be hard to say before release of fix...

Alexandre

[mkoller]

I assume nobody can force you to install a patch you don't like.

[adaneau]

That's true on Linux :laugh:

I am afraid that Microsoft will not make it so easy...

[leoknipp]

Hello Alexandre,

even if I do not know the system you are working on I'm pretty sure that you are not using a system with a constant load of 40.000 VC/sec which need to be handled by the Event Manager. If the PLC is generating such a high amount of data normally not all value changes will be sent from the driver to the Event Manager.

Normally a WinCC OA system is running nearly in idle condition, e.g with a maximum constant load for a single process of 10-15%.
If know 30 percent of the performance is lost, the process will use 13-18%, which is not a real problem from my point of view.

How we will deal with this issue and if there is a need for further investigation we have to clarify with the Product Management and Head of Development.
Please be patient and wait for further information.

Before thinking about a negative effect on your system you should check what the real load (CPU/memory, VC/sec) in your system is.
If you need more detailed information of if have made some measuerments in a real system you can get in direct with ETM for further discussions.

Best Regards
Leopold Knipp
Senior Support Specialist

[adaneau]

Hi Leo,

Thanks for your answer, I'll wait for further information from your side.