In fact, pre-allocating can save some headaches if you know the data structure is going to be a very large one, qv:

mem usage

Pay close attention to what ikegami says in this part:

Re^4: mem usage

As this sort of hack made a very real difference -- it is not simply a matter of setting the number of slots.

In reply to Re^2: Minimum Hash keys allocated? by halfcountplus
in thread Minimum Hash keys allocated? by flexvault

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