view tests/test-dirstate-race.t @ 25691:5cda0ce05c42

wireproto: add config knob for http header length limit

Well-behaved Mercurial clients will respect the httpheader capability by not
sending http headers longer than the given limit in bytes. The limit is
currently hard-coded at 1024 bytes, a safe value for any web server.

Since parsing headers is a notable factor in web server performance, tuning
header size can nontrivially improve performance for request-heavy operations
(eg. obsolete marker negotiation). Exposing the maximum header length limit
as a configuration setting is a simple way to enable such tuning.

  $ hg init
  $ echo a > a
  $ hg add a
  $ hg commit -m test

Do we ever miss a sub-second change?:

  $ for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20; do
  >     hg co -qC 0
  >     echo b > a
  >     hg st
  > done
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a