D656: revset: remove "small" argument from "_optimize"

[yuja (Yuya Nishihara)]

yuja accepted this revision.
yuja added a comment.
This revision is now accepted and ready to land.


  Queued, thanks.
  
  (copied from the email thread)
  
  On Fri, 8 Sep 2017 17:06:12 +0000, quark (Jun Wu) wrote:
  
  >> yuja wrote in revsetlang.py:421
  >  > Any reason to choose 1 here and 0.5 for the others?
  > 
  > I think there are 2 factors deciding weight:
  > 
  > 1. Time complexity of the revset implementation
  > 2. The returned revset size (maybe more important for `and` optimization)
  > 
  >   Here, `:` returns a larger revset so its weight is larger.
  
  I don't think keeping (2) makes much sense because this patch effectively
  removes the concept about the computed size. And it's far from being accurate
  anyway. In theory, the computed size would be an input to the weight function
  of the subsequent query, e.g.
  
    W_contains(subset) = K_contains * estimated_size(subset)
  
  That said, I don't have strong preference about this. So can you update the
  commit message to include why 0.5 or 1.

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D656

To: quark, #hg-reviewers, yuja
Cc: yuja, mercurial-devel