Currently, we create a logger for every compute context that is evaluated,
even when we don't actually log anything in that context (due to other
optimizations). Now, the logger is not created eagerly anymore.
This can be especially benefitial when there are many compute contexts
that should not log anything, e.g. if there is a repeat zone with many iterations.
In an extrem case I measured a speedup for the modifier evaluation
from 24ms to 14ms.
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