D477: revlog: add option to mmap revlog index

[durin42 (Augie Fackler)]

durin42 requested changes to this revision.
durin42 added a comment.
This revision now requires changes to proceed.


  Please include benchmark numbers in your commit message.

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D477

To: mbthomas, #fbhgext, indygreg, #hg-reviewers, durin42, quark
Cc: quark, durin42, simonfar, mercurial-devel