Ubisoft GDC Presentation of PS4 & X1 GPU & CPU Performance

[ICStats]

walsufnir said:

ICStats said:

walsufnir said:

ethomaz said:

mornelithe said:

You mean last year, before Microsoft bumped the clock up 10%?  And this year...after the bump, it shows differently?  No way!

Or after June SDK that free up the Kinect use of the CPU :D

1. The first benchmark arose when consoles already launched. So it was after the upclock.

2. Kinect freed gpu resources, not CPU. A shame ethomaz, as you want to sell us yourself as a hardware specialist and then you come up with this.

 

Either way, there is clearly data missing to explain numbers to us further.

This benchmark gives the performance for "5 milliseconds", in other words it is peak CPU performance without system overhead, and it is in line with the XB1's faster CPU clock speed.  The reason XB1 came short overall is because of system overhead (for Kinect voice recognition, multiple OS, snap, etc.).

 

What? So you say the system overhead fluctuates, let's say, every ten ms? That's most likely not true and I would be glad to be told otherwise with data.

Sure, it does.  System overhead is some amount of time on a core per frame.  Some of it will be in a burst like some 'ms' at the end of a frame; some of it just background tasks.

If you're doing a 5ms CPU benchmark then system overhead should be unnoticeable since the are 4 cores.  System will take one, and the benchmark should run on another with little contention.  You would see the overhead when you try to pack all 4 cores like in a full game.

The point of doing these measures like "number of dancers in 5ms" is for budgeting.  You have some budget per frame, say for Ubisoft's 30fps games the amount of CPU time per frame is (4 * 33.3ms - System_Overhead).  Their benchmark tells them how many dancers they can do per ms, but you have to count system overhead to determine number of dancers per frame.