How to measure Active RAM usage?

[Mr.Briggs]

I do not mean the capacity of memory currently in use.

What i want to measure is, what is the active usage on my ram? e.g. if i have 6gb used of 16gb total, how do i know if i'm being bottlenecked by ram speed?

I previously upgraded a laptop to dual channel and seen fps go from ~30 to ~50, with a significant reduction in CPU usage, which can only mean that slower ram = higher cpu 'active time'?

Ideally I'd love to see a 'current bandwidth usage' or something, beside ram usage.

Can anyone shed any light on this?

Many thanks!

[Alex Atkin UK]

50 minutes ago, Mr.Briggs said:

I previously upgraded a laptop to dual channel and seen fps go from ~30 to ~50, with a significant reduction in CPU usage, which can only mean that slower ram = higher cpu 'active time'?

Its more than if the CPU is waiting for data from RAM, it can't do anything else in the meantime so will be reported as 100% usage.  Whereas with more bandwidth, it will finish what its doing faster, so free up CPU time.

 

Its actually quite easy to make a CPU core 100% busy while its actually doing absolutely nothing.  In fact the NVIDIA drivers do this as a way to reserve a single CPU core for the drivers to use exclusively, so driver tasks never get stalled waiting for spare CPU time from other tasks.

[Mr.Briggs]

2 hours ago, Alex Atkin UK said:

Its more than if the CPU is waiting for data from RAM, it can't do anything else in the meantime so will be reported as 100% usage.  Whereas with more bandwidth, it will finish what its doing faster, so free up CPU time.

 

Its actually quite easy to make a CPU core 100% busy while its actually doing absolutely nothing.  In fact the NVIDIA drivers do this as a way to reserve a single CPU core for the drivers to use exclusively, so driver tasks never get stalled waiting for spare CPU time from other tasks.

that is very interesting! thank you.

Im wondering if there is a way to measure or visualise the additional cpu time caused by waiting on RAM