Timeloop mapper constraint output

[Yukiona1996]

Hi,

On running the timeloop-mapper with a mapping constraint, what does the utilisation that is rendered at the end of the execution refer to? Is it utilisation of the PE's? Or does it refer the reuse of data?

Thanks!

[angshuman-parashar]

Arithmetic unit utilization. It's affected by (1) spatial utilization, i.e., the % of arithmetic units that have work mapped onto them (determined by spatial fanout factors) and (2) temporal utilization, i.e., the average % of cycles the units were busy (which can be less than 100% if the mapping is bandwidth-throttled by data movement).

[Yukiona1996]

That would mean the problem defined as,
problem:
instance:
C: 128
Hdilation: 1
Hstride: 1
M: 256
N: 1
P: 56
Q: 56
R: 3
S: 3
Wdilation: 1
Wstride: 1

P and Q defines the spatial dimensions?

[angshuman-parashar]

No. This is an unmapped problem that has not been mapped over space or time. If you haven't done so already, I recommend watching our video tutorials. They explain how the dimensions of an unmapped problem are broken into tiles and subsequently projected onto hardware space and time using a mapping.