comparison mercurial/utils/storageutil.py @ 49609:9cac281eb9c0

debug: add an option to display statistic about a bundling operation

This will helps a lot to understand how the bundling decision might impact
pull/unbundle on the other side.

49608:78ba41878f2e

    flagsfn=None,
    deltamode=repository.CG_DELTAMODE_STD,
    revisiondata=False,
    assumehaveparentrevisions=False,
    sidedata_helpers=None,
):
    """Generic implementation of ifiledata.emitrevisions().

    Emitting revision data is subtly complex. This function attempts to
    encapsulate all the logic for doing so in a backend-agnostic way.

    ``revisiondata``
    ``assumehaveparentrevisions``
    ``sidedata_helpers`` (optional)
        If not None, means that sidedata should be included.
        See `revlogutil.sidedata.get_sidedata_helpers`.
    """

    fnode = store.node
    frev = store.rev

    for rev in revs:
        if rev == nullrev:
            continue

        node = fnode(rev)
        p1rev, p2rev = store.parentrevs(rev)

        if deltaparentfn:
            deltaparentrev = deltaparentfn(rev)
        else:
            deltaparentrev = nullrev

        # Forced delta against previous mode.
        if deltamode == repository.CG_DELTAMODE_PREV:
            baserev = prevrev

        # We're instructed to send fulltext. Honor that.
        elif deltamode == repository.CG_DELTAMODE_FULL:
            baserev = nullrev
        # We're instructed to use p1. Honor that
        elif deltamode == repository.CG_DELTAMODE_P1:
            baserev = p1rev

        # There is a delta in storage. We try to use that because it
        # amounts to effectively copying data from storage and is
        # therefore the fastest.
        elif deltaparentrev != nullrev:
            # Base revision was already emitted in this group. We can
            # always safely use the delta.
            if deltaparentrev in available:
                baserev = deltaparentrev

            # Base revision is a parent that hasn't been emitted already.
            # Use it if we can assume the receiver has the parent revision.
            elif assumehaveparentrevisions and deltaparentrev in (p1rev, p2rev):
                baserev = deltaparentrev

            # No guarantee the receiver has the delta parent. Send delta
            # against last revision (if possible), which in the common case
            # should be similar enough to this revision that the delta is
            # reasonable.
            elif prevrev is not None:
                baserev = prevrev
            else:
                baserev = nullrev

        # Storage has a fulltext revision.

        # Let's use the previous revision, which is as good a guess as any.
        # There is definitely room to improve this logic.
        elif prevrev is not None:
            baserev = prevrev
        else:
            baserev = nullrev

        # But we can't actually use our chosen delta base for whatever
        # reason. Reset to fulltext.
        if baserev != nullrev and (candeltafn and not candeltafn(baserev, rev)):
            baserev = nullrev

        revision = None
        delta = None
        baserevisionsize = None

        if revisiondata:
            if store.iscensored(baserev) or store.iscensored(rev):
                try:
                    revision = store.rawdata(node)
                except error.CensoredNodeError as e:
                    revision = e.tombstone

                if baserev != nullrev:
                    if rawsizefn:
                        baserevisionsize = rawsizefn(baserev)

                        baserevisionsize = len(store.rawdata(baserev))

            elif (
                baserev == nullrev and deltamode != repository.CG_DELTAMODE_PREV
            ):
                revision = store.rawdata(node)
                available.add(rev)
            else:
                if revdifffn:
                    delta = revdifffn(baserev, rev)
                else:
                    delta = mdiff.textdiff(
                        store.rawdata(baserev), store.rawdata(rev)
                    )

                available.add(rev)

49609:9cac281eb9c0

    flagsfn=None,
    deltamode=repository.CG_DELTAMODE_STD,
    revisiondata=False,
    assumehaveparentrevisions=False,
    sidedata_helpers=None,
    debug_info=None,
):
    """Generic implementation of ifiledata.emitrevisions().

    Emitting revision data is subtly complex. This function attempts to
    encapsulate all the logic for doing so in a backend-agnostic way.

    ``revisiondata``
    ``assumehaveparentrevisions``
    ``sidedata_helpers`` (optional)
        If not None, means that sidedata should be included.
        See `revlogutil.sidedata.get_sidedata_helpers`.

    ``debug_info`
        An optionnal dictionnary to gather information about the bundling
        process (if present, see config: debug.bundling.stats.
    """

    fnode = store.node
    frev = store.rev

    for rev in revs:
        if rev == nullrev:
            continue

        debug_delta_source = None
        if debug_info is not None:
            debug_info['revision-total'] += 1

        node = fnode(rev)
        p1rev, p2rev = store.parentrevs(rev)

        if debug_info is not None:
            if p1rev != p2rev and p1rev != nullrev and p2rev != nullrev:
                debug_info['merge-total'] += 1

        if deltaparentfn:
            deltaparentrev = deltaparentfn(rev)
            if debug_info is not None:
                if deltaparentrev == nullrev:
                    debug_info['available-full'] += 1
                else:
                    debug_info['available-delta'] += 1

        else:
            deltaparentrev = nullrev

        # Forced delta against previous mode.
        if deltamode == repository.CG_DELTAMODE_PREV:
            if debug_info is not None:
                debug_delta_source = "prev"
            baserev = prevrev

        # We're instructed to send fulltext. Honor that.
        elif deltamode == repository.CG_DELTAMODE_FULL:
            if debug_info is not None:
                debug_delta_source = "full"
            baserev = nullrev
        # We're instructed to use p1. Honor that
        elif deltamode == repository.CG_DELTAMODE_P1:
            if debug_info is not None:
                debug_delta_source = "p1"
            baserev = p1rev

        # There is a delta in storage. We try to use that because it
        # amounts to effectively copying data from storage and is
        # therefore the fastest.
        elif deltaparentrev != nullrev:
            # Base revision was already emitted in this group. We can
            # always safely use the delta.
            if deltaparentrev in available:
                if debug_info is not None:
                    debug_delta_source = "storage"
                baserev = deltaparentrev

            # Base revision is a parent that hasn't been emitted already.
            # Use it if we can assume the receiver has the parent revision.
            elif assumehaveparentrevisions and deltaparentrev in (p1rev, p2rev):
                if debug_info is not None:
                    debug_delta_source = "storage"
                baserev = deltaparentrev
            # No guarantee the receiver has the delta parent. Send delta
            # against last revision (if possible), which in the common case
            # should be similar enough to this revision that the delta is
            # reasonable.
            elif prevrev is not None:
                if debug_info is not None:
                    debug_info['denied-base-not-available'] += 1
                    debug_delta_source = "prev"
                baserev = prevrev
            else:
                if debug_info is not None:
                    debug_info['denied-base-not-available'] += 1
                    debug_delta_source = "full"
                baserev = nullrev

        # Storage has a fulltext revision.

        # Let's use the previous revision, which is as good a guess as any.
        # There is definitely room to improve this logic.
        elif prevrev is not None:
            if debug_info is not None:
                debug_delta_source = "prev"
            baserev = prevrev
        else:
            if debug_info is not None:
                debug_delta_source = "full"
            baserev = nullrev

        # But we can't actually use our chosen delta base for whatever
        # reason. Reset to fulltext.
        if (
            baserev != nullrev
            and candeltafn is not None
            and not candeltafn(baserev, rev)
        ):
            if debug_info is not None:
                debug_delta_source = "full"
                debug_info['denied-delta-candeltafn'] += 1
            baserev = nullrev

        revision = None
        delta = None
        baserevisionsize = None

        if revisiondata:
            if store.iscensored(baserev) or store.iscensored(rev):
                try:
                    revision = store.rawdata(node)
                except error.CensoredNodeError as e:
                    if debug_info is not None:
                        debug_delta_source = "full"
                        debug_info['denied-delta-not-available'] += 1
                    revision = e.tombstone

                if baserev != nullrev:
                    if rawsizefn:
                        baserevisionsize = rawsizefn(baserev)

                        baserevisionsize = len(store.rawdata(baserev))

            elif (
                baserev == nullrev and deltamode != repository.CG_DELTAMODE_PREV
            ):
                if debug_info is not None:
                    debug_info['computed-delta'] += 1  # close enough
                    debug_info['delta-full'] += 1
                revision = store.rawdata(node)
                available.add(rev)
            else:
                if revdifffn:
                    if debug_info is not None:
                        if debug_delta_source == "full":
                            debug_info['computed-delta'] += 1
                            debug_info['delta-full'] += 1
                        elif debug_delta_source == "prev":
                            debug_info['computed-delta'] += 1
                            debug_info['delta-against-prev'] += 1
                        elif debug_delta_source == "p1":
                            debug_info['computed-delta'] += 1
                            debug_info['delta-against-p1'] += 1
                        elif debug_delta_source == "storage":
                            debug_info['reused-storage-delta'] += 1
                        else:
                            assert False, 'unreachable'

                    delta = revdifffn(baserev, rev)
                else:
                    if debug_info is not None:
                        if debug_delta_source == "full":
                            debug_info['computed-delta'] += 1
                            debug_info['delta-full'] += 1
                        elif debug_delta_source == "prev":
                            debug_info['computed-delta'] += 1
                            debug_info['delta-against-prev'] += 1
                        elif debug_delta_source == "p1":
                            debug_info['computed-delta'] += 1
                            debug_info['delta-against-p1'] += 1
                        elif debug_delta_source == "storage":
                            # seem quite unlikelry to happens
                            debug_info['computed-delta'] += 1
                            debug_info['reused-storage-delta'] += 1
                        else:
                            assert False, 'unreachable'
                    delta = mdiff.textdiff(
                        store.rawdata(baserev), store.rawdata(rev)
                    )

                available.add(rev)