# Constant QPU access time from CQM model

Hello, I am enjoying D-wave CQM model for solving various problems.

I have a question about QPU access time of CQM model.

I used the CQM for solving 16 Integer variables with the range of 40,000 which can be accommodated by CQM model.

I found that as the time_limit parameter, which limits the maximum run time, of CQM model gets larger problem accuracy gets better for the same condition. I thought sufficient annealing time resulted in an accurate answer(minimizied objective value), which converged after some value of the time_limit parameter as it went larger. However the QPU access times that the sample gave were always constant, regardless of the value of the time_limit parameter. No matter how big the time_limit parameter is, QPU access time for CQM model gave me the almost same value of 0.032 ms. (I referred the QPU access time from ' sample.info ')

Since the CQM model doesn't provide any details or breakdown of QPU access time, unlike BQM model, I have no idea why problem accuracy gets better, if QPU access time does not increase. I know the algorithm of CQM in detail can not be presented, but if it is possible, I want to understand the picture of why the problem accuracy changes along the time_limit.

Thank you.

## Comments

David J(Report)Hello,

Classical compute resources are used alongside Quantum resources, so which accounts for change in solution as the

time_limitincreases.As needed Quantum compute resources are used so eventually there will be more QPU usage returned at some point.

I hope this helps answer your question.

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