comparison mercurial/bundle2.py @ 46372:3e91d9978bec

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

46371:0903d6b9b1df

rbcstruct = struct.Struct(b'>III')


@parthandler(b'cache:rev-branch-cache')
def handlerbc(op, inpart):
    """receive a rev-branch-cache payload and update the local cache

    The payload is a series of data related to each branch

    1) branch name length
    2) number of open heads
    3) number of closed heads
    4) open heads nodes
    5) closed heads nodes
    """
    total = 0
    rawheader = inpart.read(rbcstruct.size)
    cache = op.repo.revbranchcache()
    cl = op.repo.unfiltered().changelog
    while rawheader:
        header = rbcstruct.unpack(rawheader)
        total += header[1] + header[2]
        utf8branch = inpart.read(header[0])
        branch = encoding.tolocal(utf8branch)
        for x in pycompat.xrange(header[1]):
            node = inpart.read(20)
            rev = cl.rev(node)
            cache.setdata(branch, rev, node, False)
        for x in pycompat.xrange(header[2]):
            node = inpart.read(20)
            rev = cl.rev(node)
            cache.setdata(branch, rev, node, True)
        rawheader = inpart.read(rbcstruct.size)
    cache.write()


@parthandler(b'pushvars')
def bundle2getvars(op, part):
    '''unbundle a bundle2 containing shellvars on the server'''

46372:3e91d9978bec

rbcstruct = struct.Struct(b'>III')


@parthandler(b'cache:rev-branch-cache')
def handlerbc(op, inpart):
    """Legacy part, ignored for compatibility with bundles from or
    for Mercurial before 5.7. Newer Mercurial computes the cache
    efficiently enough during unbundling that the additional transfer
    is unnecessary."""


@parthandler(b'pushvars')
def bundle2getvars(op, part):
    '''unbundle a bundle2 containing shellvars on the server'''