Mercurial > hg
view mercurial/dirstateutils/docket.py @ 51594:e3a5ec2d236a
outgoing: rework the handling of the `missingroots` case to be faster
The previous implementation was slow, to the point it was taking a significant
amount of `hg bundle --type none-streamv2` call. We rework the code to compute
the same value much faster, making the operation disappear from the `hg bundle
--type none-streamv2` profile. Someone would remark that producing a streamclone
does not requires an `outgoing` object. However that is a matter for another
day. There is other user of `missingroots` (non stream `hg bundle` call for
example), and they will also benefit from this rework.
We implement an old TODO in the process, directly computing the missing and
common attribute as we have most element at hand already.
### benchmark.name = hg.command.bundle
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.revs = all
# benchmark.variants.type = none-streamv2
## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog
before: 7.750458
after: 6.665565 (-14.00%, -1.08)
## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog
before: 0.700229
after: 0.496050 (-29.16%, -0.20)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
before: 346.508952
after: 316.749699 (-8.59%, -29.76)
## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
before: 3.401700
after: 2.915810 (-14.28%, -0.49)
## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog
before: 1.870798
after: 1.461583 (-21.87%, -0.41)
note: this whole `missingroots` of outgoing has a limited number of callers and
could likely be replace by something simpler (like taking an explicit
"missing_revs" set for example). However this is a wider change and we focus on
a small impact, quick rework that does not change the API for now.
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Tue, 09 Apr 2024 22:36:35 +0200 |
parents | 642e31cb55f0 |
children | f4733654f144 |
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# dirstatedocket.py - docket file for dirstate-v2 # # Copyright Mercurial Contributors # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. import struct from ..revlogutils import docket as docket_mod from . import v2 V2_FORMAT_MARKER = b"dirstate-v2\n" # * 12 bytes: format marker # * 32 bytes: node ID of the working directory's first parent # * 32 bytes: node ID of the working directory's second parent # * {TREE_METADATA_SIZE} bytes: tree metadata, parsed separately # * 4 bytes: big-endian used size of the data file # * 1 byte: length of the data file's UUID # * variable: data file's UUID # # Node IDs are null-padded if shorter than 32 bytes. # A data file shorter than the specified used size is corrupted (truncated) HEADER = struct.Struct( ">{}s32s32s{}sLB".format(len(V2_FORMAT_MARKER), v2.TREE_METADATA_SIZE) ) class DirstateDocket: data_filename_pattern = b'dirstate.%s' def __init__(self, parents, data_size, tree_metadata, uuid): self.parents = parents self.data_size = data_size self.tree_metadata = tree_metadata self.uuid = uuid @classmethod def with_new_uuid(cls, parents, data_size, tree_metadata): return cls(parents, data_size, tree_metadata, docket_mod.make_uid()) @classmethod def parse(cls, data, nodeconstants): if not data: parents = (nodeconstants.nullid, nodeconstants.nullid) return cls(parents, 0, b'', None) marker, p1, p2, meta, data_size, uuid_size = HEADER.unpack_from(data) if marker != V2_FORMAT_MARKER: raise ValueError("expected dirstate-v2 marker") uuid = data[HEADER.size : HEADER.size + uuid_size] p1 = p1[: nodeconstants.nodelen] p2 = p2[: nodeconstants.nodelen] return cls((p1, p2), data_size, meta, uuid) def serialize(self): p1, p2 = self.parents header = HEADER.pack( V2_FORMAT_MARKER, p1, p2, self.tree_metadata, self.data_size, len(self.uuid), ) return header + self.uuid def data_filename(self): return self.data_filename_pattern % self.uuid