branchmap: update rev-branch-cache incrementally
Historically, the revision to branch mapping cache was updated on demand
and shared via bundle2 to avoid the cost of rebuilding on first use.
Use the new `register_changeset` callback and update rbc directly on
every change. Make the transfer of the bundle part redundant, but keep
it for the moment to avoid the test churn.
Over all, "hg unbundle" for large bundles is less than 1.8% slower for
different larger repositories and that seems to a reasonable trade off.
Differential Revision: https://phab.mercurial-scm.org/D9781
#!/usr/bin/env python3
from __future__ import absolute_import
__doc__ = """Same as `echo a >> b`, but ensures a changed mtime of b.
Without this svn will not detect workspace changes."""
import os
import stat
import sys
if sys.version_info[0] >= 3:
text = os.fsencode(sys.argv[1])
fname = os.fsencode(sys.argv[2])
else:
text = sys.argv[1]
fname = sys.argv[2]
f = open(fname, "ab")
try:
before = os.fstat(f.fileno())[stat.ST_MTIME]
f.write(text)
f.write(b"\n")
finally:
f.close()
inc = 1
now = os.stat(fname)[stat.ST_MTIME]
while now == before:
t = now + inc
inc += 1
os.utime(fname, (t, t))
now = os.stat(fname)[stat.ST_MTIME]