view contrib/undumprevlog @ 40374:47c03042cd1d

branchmap: pass changelog into branchmap functions

As part of building the branchmap, we loop over revs and call branchmap()
or _branchmap(). Previously, these functions were accessing repo.changelog.
We know from past experience that repo.changelog in loops is bad for
performance.

This commit teaches the branchmap code to pass a changelog instance into
branchmap() and _branchmap() so we don't need to pay this penalty.

On my MBP, this appears to show a speedup on a clone of the
mozilla-unified repo:

$ hg perfbranchmap --clear-revbranch
! base
! wall 21.078160 comb 21.070000 user 20.920000 sys 0.150000 (best of 3)
! wall 20.574682 comb 20.560000 user 20.400000 sys 0.160000 (best of 3)

$ hg perfbranchmap
! base
! wall 4.880413 comb 4.870000 user 4.860000 sys 0.010000 (best of 3)
! wall 4.573968 comb 4.560000 user 4.550000 sys 0.010000 (best of 3)

Differential Revision: https://phab.mercurial-scm.org/D5161

#!/usr/bin/env python
# Undump a dump from dumprevlog
# $ hg init
# $ undumprevlog < repo.dump

from __future__ import absolute_import, print_function

import sys
from mercurial import (
    encoding,
    node,
    pycompat,
    revlog,
    transaction,
    vfs as vfsmod,
)
from mercurial.utils import (
    procutil,
)

for fp in (sys.stdin, sys.stdout, sys.stderr):
    procutil.setbinary(fp)

opener = vfsmod.vfs(b'.', False)
tr = transaction.transaction(sys.stderr.write, opener, {b'store': opener},
                             b"undump.journal")
while True:
    l = sys.stdin.readline()
    if not l:
        break
    if l.startswith("file:"):
        f = encoding.strtolocal(l[6:-1])
        r = revlog.revlog(opener, f)
        pycompat.stdout.write(b'%s\n' % f)
    elif l.startswith("node:"):
        n = node.bin(l[6:-1])
    elif l.startswith("linkrev:"):
        lr = int(l[9:-1])
    elif l.startswith("parents:"):
        p = l[9:-1].split()
        p1 = node.bin(p[0])
        p2 = node.bin(p[1])
    elif l.startswith("length:"):
        length = int(l[8:-1])
        sys.stdin.readline() # start marker
        d = encoding.strtolocal(sys.stdin.read(length))
        sys.stdin.readline() # end marker
        r.addrevision(d, tr, lr, p1, p2)

tr.close()