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View Full Version : Cpu usage, Total does not mean total?


Rockman413
06-02-2017, 04:38 AM
Hi there,
So I'm very much into performance. When running at lower buffer size, I watch the CPU usage and find an interesting thing:

When all the cores are under 50%, sometimes the Total reaches 100%, WHY?
Can the expert who knows this tell us? Why all cores are under 50% but total could reach 100%? Isn't the total should be the average of all cores? What does Total means?
Why sometimes there's a tiny red label "|" to the right of total, and when that red "|" reaches 100% there's clicks&pops even though the yellow total is only 50%, why?

Thanks

LightWing
06-04-2017, 04:02 AM
VERY good question. I see this ALOT.

eesn
06-05-2017, 12:58 AM
PT is only some of everything the CPU executes. PT's audio is only part of everything PT runs when active. Think playing and scrolling on an integrated graphics GPU/CPU.

Then there's threading, where meaningful values go to N x 100%, N being the number of of cores. Then there's hyperthreading, which means each core can often run up to two threads at full speed, but rarely two at full speed, my experience is 1 at 100% and 1 at 50% tops.

I guess "it's complicated" isn't too out of place to say. That said, find a value at which things no longer "work" and simply avoid it.

PT10 for instance had a habit of engaging all DSP code always at all times. I don't remember CPU load fluctuating w/ PT10. Made a nice little heater of the computer, even when not playing, or with plugins on empty tracks..