comparison mercurial/branchmap.py @ 51536:718f28ea3af4

branchcache: add a "pure topological head" fast path

In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.

So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.

The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.

51535:03247e37ccf7

        self._per_filter = {}

    def __getitem__(self, repo):
        self.updatecache(repo)
        bcache = self._per_filter[repo.filtername]
        assert bcache._filtername == repo.filtername, (
            bcache._filtername,
            repo.filtername,
        )
        return bcache

            self._hasnode = repo.changelog.hasnode

    def _compute_key_hashes(self, repo) -> Tuple[bytes]:
        raise NotImplementedError

    def validfor(self, repo):
        """check that cache contents are valid for (a subset of) this repo

        - False when the order of changesets changed or if we detect a strip.
        - True when cache is up-to-date for the current repo or its subset."""

    """

    _base_filename = b"branch3"
    _default_key_hashes = (None, None)

    def _get_topo_heads(self, repo) -> List[int]:
        """returns the topological head of a repoview content up to self.tiprev"""
        cl = repo.changelog
        if self.tiprev == nullrev:
            return []
        elif self.tiprev == cl.tiprev():

        if self.key_hashes:
            if self.key_hashes[0] is not None:
                cache_keys[b"filtered-hash"] = hex(self.key_hashes[0])
            if self.key_hashes[1] is not None:
                cache_keys[b"obsolete-hash"] = hex(self.key_hashes[1])
        pieces = (b"%s=%s" % i for i in sorted(cache_keys.items()))
        fp.write(b" ".join(pieces) + b'\n')

    def _write_heads(self, repo, fp) -> int:
        """write list of heads to a file

        Return the number of heads written."""
        nodecount = 0
        topo_heads = set(self._get_topo_heads(repo))
        to_rev = repo.changelog.index.rev
        for label, nodes in sorted(self._entries.items()):
            label = encoding.fromlocal(label)
            for node in nodes:
                rev = to_rev(node)
                if rev in topo_heads:
                    continue
                if node in self._closednodes:
                    state = b'c'
                else:
                    state = b'o'
                nodecount += 1

        cache_keys = dict(p.split(b'=', 1) for p in pieces)

        args = {}
        filtered_hash = None
        obsolete_hash = None
        for k, v in cache_keys.items():
            if k == b"tip-rev":
                args["tiprev"] = int(v)
            elif k == b"tip-node":
                args["tipnode"] = bin(v)
            elif k == b"filtered-hash":
                filtered_hash = bin(v)
            elif k == b"obsolete-hash":
                obsolete_hash = bin(v)
            else:
                msg = b"unknown cache key: %r" % k
                raise ValueError(msg)
        args["key_hashes"] = (filtered_hash, obsolete_hash)
        return args

    def _load_heads(self, repo, lineiter):
        """fully loads the branchcache by reading from the file using the line
        iterator passed"""
        super()._load_heads(repo, lineiter)
        cl = repo.changelog
        getbranchinfo = repo.revbranchcache().branchinfo
        obsrevs = obsolete.getrevs(repo, b'obsolete')
        to_node = cl.node
        touched_branch = set()

        """return the cache key hashes that match this repoview state"""
        return scmutil.filtered_and_obsolete_hash(
            repo,
            self.tiprev,
        )


class remotebranchcache(_BaseBranchCache):
    """Branchmap info for a remote connection, should not write locally"""

51536:718f28ea3af4

        self._per_filter = {}

    def __getitem__(self, repo):
        self.updatecache(repo)
        bcache = self._per_filter[repo.filtername]
        bcache._ensure_populated(repo)
        assert bcache._filtername == repo.filtername, (
            bcache._filtername,
            repo.filtername,
        )
        return bcache

            self._hasnode = repo.changelog.hasnode

    def _compute_key_hashes(self, repo) -> Tuple[bytes]:
        raise NotImplementedError

    def _ensure_populated(self, repo):
        """make sure any lazily loaded values are fully populated"""

    def validfor(self, repo):
        """check that cache contents are valid for (a subset of) this repo

        - False when the order of changesets changed or if we detect a strip.
        - True when cache is up-to-date for the current repo or its subset."""

    """

    _base_filename = b"branch3"
    _default_key_hashes = (None, None)

    def __init__(self, *args, pure_topo_branch=None, **kwargs):
        super().__init__(*args, **kwargs)
        self._pure_topo_branch = pure_topo_branch
        self._needs_populate = self._pure_topo_branch is not None

    def inherit_for(self, repo):
        new = super().inherit_for(repo)
        new._pure_topo_branch = self._pure_topo_branch
        new._needs_populate = self._needs_populate
        return new

    def _get_topo_heads(self, repo):
        """returns the topological head of a repoview content up to self.tiprev"""
        cl = repo.changelog
        if self.tiprev == nullrev:
            return []
        elif self.tiprev == cl.tiprev():

        if self.key_hashes:
            if self.key_hashes[0] is not None:
                cache_keys[b"filtered-hash"] = hex(self.key_hashes[0])
            if self.key_hashes[1] is not None:
                cache_keys[b"obsolete-hash"] = hex(self.key_hashes[1])
        if self._pure_topo_branch is not None:
            cache_keys[b"topo-mode"] = b"pure"
        pieces = (b"%s=%s" % i for i in sorted(cache_keys.items()))
        fp.write(b" ".join(pieces) + b'\n')
        if self._pure_topo_branch is not None:
            label = encoding.fromlocal(self._pure_topo_branch)
            fp.write(label + b'\n')

    def _write_heads(self, repo, fp) -> int:
        """write list of heads to a file

        Return the number of heads written."""
        nodecount = 0
        topo_heads = None
        if self._pure_topo_branch is None:
            topo_heads = set(self._get_topo_heads(repo))
        to_rev = repo.changelog.index.rev
        for label, nodes in sorted(self._entries.items()):
            if label == self._pure_topo_branch:
                # not need to write anything the header took care of that
                continue
            label = encoding.fromlocal(label)
            for node in nodes:
                if topo_heads is not None:
                    rev = to_rev(node)
                    if rev in topo_heads:
                        continue
                if node in self._closednodes:
                    state = b'c'
                else:
                    state = b'o'
                nodecount += 1

        cache_keys = dict(p.split(b'=', 1) for p in pieces)

        args = {}
        filtered_hash = None
        obsolete_hash = None
        has_pure_topo_heads = False
        for k, v in cache_keys.items():
            if k == b"tip-rev":
                args["tiprev"] = int(v)
            elif k == b"tip-node":
                args["tipnode"] = bin(v)
            elif k == b"filtered-hash":
                filtered_hash = bin(v)
            elif k == b"obsolete-hash":
                obsolete_hash = bin(v)
            elif k == b"topo-mode":
                if v == b"pure":
                    has_pure_topo_heads = True
                else:
                    msg = b"unknown topo-mode: %r" % v
                    raise ValueError(msg)
            else:
                msg = b"unknown cache key: %r" % k
                raise ValueError(msg)
        args["key_hashes"] = (filtered_hash, obsolete_hash)
        if has_pure_topo_heads:
            pure_line = next(lineiter).rstrip(b'\n')
            args["pure_topo_branch"] = encoding.tolocal(pure_line)
        return args

    def _load_heads(self, repo, lineiter):
        """fully loads the branchcache by reading from the file using the line
        iterator passed"""
        super()._load_heads(repo, lineiter)
        if self._pure_topo_branch is not None:
            # no need to read the repository heads, we know their value already.
            return
        cl = repo.changelog
        getbranchinfo = repo.revbranchcache().branchinfo
        obsrevs = obsolete.getrevs(repo, b'obsolete')
        to_node = cl.node
        touched_branch = set()

        """return the cache key hashes that match this repoview state"""
        return scmutil.filtered_and_obsolete_hash(
            repo,
            self.tiprev,
        )

    def _process_new(
        self,
        repo,
        newbranches,
        new_closed,
        obs_ignored,
        max_rev,
    ) -> None:
        if (
            # note: the check about `obs_ignored` is too strict as the
            # obsolete revision could be non-topological, but lets keep
            # things simple for now
            #
            # The same apply to `new_closed` if the closed changeset are
            # not a head, we don't care that it is closed, but lets keep
            # things simple here too.
            not (obs_ignored or new_closed)
            and (
                not newbranches
                or (
                    len(newbranches) == 1
                    and (
                        self.tiprev == nullrev
                        or self._pure_topo_branch in newbranches
                    )
                )
            )
        ):
            if newbranches:
                assert len(newbranches) == 1
                self._pure_topo_branch = list(newbranches.keys())[0]
                self._needs_populate = True
                self._entries.pop(self._pure_topo_branch, None)
            return

        self._ensure_populated(repo)
        self._pure_topo_branch = None
        super()._process_new(
            repo,
            newbranches,
            new_closed,
            obs_ignored,
            max_rev,
        )

    def _ensure_populated(self, repo):
        """make sure any lazily loaded values are fully populated"""
        if self._needs_populate:
            assert self._pure_topo_branch is not None
            cl = repo.changelog
            to_node = cl.node
            topo_heads = self._get_topo_heads(repo)
            heads = [to_node(r) for r in topo_heads]
            self._entries[self._pure_topo_branch] = heads
            self._needs_populate = False


class remotebranchcache(_BaseBranchCache):
    """Branchmap info for a remote connection, should not write locally"""