BasisTranslator, Decompose, BarrierBeforeFinalMeasurements, DAGFixedPoint using a lot of memory

[ewinston]

What is the expected enhancement?

Running some transpiler passes for growing number circuit sizes scales reasonably however in some cases the absolute value seems rather large. The circuits in this case are random circuits of equal width and depth.

Python's tracemalloc is used to track peak memory usage during the pass. BasisTranslator, Decmpose, and DAGFixedPoint seem to use around 1 GB of peak memory by the time width=depth=1024. BarrierBeforeFinalMeasurements uses somewhat less memory but seems excessive considering the pass.