On Thu, Oct 10, 2019 at 12:02:29PM -0700, Jonathan Tan wrote:

quoted

On 10/9/2019 7:44 PM, Jonathan Tan wrote:

quoted

Instead, recompute ancestry if we ever need to reclaim memory.

I find this message lacking in important details:

1. Where do we recompute ancestry?
2. What are the performance implications of this change?
3. Why is it important that you construct a stack of deltas in prune_base_data()?

Thanks for taking a look at this. My original plan (as I perhaps badly
explained in the cover letter [1]) was to show the individual small
steps that I took to reach the end goal, each step still passing all
tests, in the hope that small steps are easier to understand than one
big one. Hence why I didn't explain much in this commit message (and
others), because I thought that I might have to squash them later. But
perhaps that is too confusing and I should have just squashed them in
the first place (and explain all the changes in the commit message -
it's +177 -198, which is not too big anyway).

FWIW, I like the breakdown. These are tricky cleanups, and seeing them
individually makes it easy to verify that they don't themselves break
anything. I think they just need more explanation.

-Peff