copies: avoid instancing more changectx to access parent revisions
We just need to know the revision numbers of the parents, creating full context
is needlessly expensive.
This provide a small, but noticeable performance boost.
revision: large amount; added files: large amount; rename small amount;
c3b14617fbd7 9ba6ab77fd29
before: ! wall 2.885636 comb 2.900000 user 2.870000 sys 0.030000 (median of 10)
after: ! wall 2.702270 comb 2.710000 user 2.690000 sys 0.020000 (median of 10)
revision: large amount; added files: small amount; rename small amount;
c3b14617fbd7 f650a9b140d2
before: ! wall 4.298271 comb 4.290000 user 4.240000 sys 0.050000 (median of 10)
after: ! wall 3.976610 comb 3.970000 user 3.920000 sys 0.050000 (median of 10)
revision: large amount; added files: large amount; rename large amount;
08ea3258278e d9fa043f30c0
before: ! wall 0.773397 comb 0.770000 user 0.770000 sys 0.000000 (median of 11)
after: ! wall 0.701634 comb 0.700000 user 0.700000 sys 0.000000 (median of 13)
revision: small amount; added files: large amount; rename large amount;
df6f7a526b60 a83dc6a2d56f
before: ! wall 0.013585 comb 0.010000 user 0.010000 sys 0.000000 (median of 217)
after: ! wall 0.013550 comb 0.010000 user 0.010000 sys 0.000000 (median of 218)
revision: small amount; added files: large amount; rename small amount;
4aa4e1f8e19a 169138063d63
before: ! wall 0.003202 comb 0.000000 user 0.000000 sys 0.000000 (median of 929)
after: ! wall 0.002993 comb 0.010000 user 0.010000 sys 0.000000 (median of 992)
revision: small amount; added files: small amount; rename small amount;
4bc173b045a6 964879152e2e
before: ! wall 0.000077 comb 0.000000 user 0.000000 sys 0.000000 (median of 12060)
after: ! wall 0.000072 comb 0.000000 user 0.000000 sys 0.000000 (median of 12804)
revision: medium amount; added files: large amount; rename medium amount;
c95f1ced15f2 2c68e87c3efe
before: ! wall 0.510614 comb 0.500000 user 0.500000 sys 0.000000 (median of 18)
after: ! wall 0.473681 comb 0.470000 user 0.470000 sys 0.000000 (median of 20)
revision: medium amount; added files: medium amount; rename small amount;
d343da0c55a8 d7746d32bf9d
before: ! wall 0.126552 comb 0.130000 user 0.130000 sys 0.000000 (median of 77)
after: ! wall 0.115240 comb 0.110000 user 0.110000 sys 0.000000 (median of 85)
Differential Revision: https://phab.mercurial-scm.org/D7122
# revlogdeltas.py - constant used for revlog logic
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
# Copyright 2018 Octobus <contact@octobus.net>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Helper class to compute deltas stored inside revlogs"""
from __future__ import absolute_import
from ..interfaces import repository
# revlog header flags
REVLOGV0 = 0
REVLOGV1 = 1
# Dummy value until file format is finalized.
# Reminder: change the bounds check in revlog.__init__ when this is changed.
REVLOGV2 = 0xDEAD
# Shared across v1 and v2.
FLAG_INLINE_DATA = 1 << 16
# Only used by v1, implied by v2.
FLAG_GENERALDELTA = 1 << 17
REVLOG_DEFAULT_FLAGS = FLAG_INLINE_DATA
REVLOG_DEFAULT_FORMAT = REVLOGV1
REVLOG_DEFAULT_VERSION = REVLOG_DEFAULT_FORMAT | REVLOG_DEFAULT_FLAGS
REVLOGV1_FLAGS = FLAG_INLINE_DATA | FLAG_GENERALDELTA
REVLOGV2_FLAGS = FLAG_INLINE_DATA
# revlog index flags
# For historical reasons, revlog's internal flags were exposed via the
# wire protocol and are even exposed in parts of the storage APIs.
# revision has censor metadata, must be verified
REVIDX_ISCENSORED = repository.REVISION_FLAG_CENSORED
# revision hash does not match data (narrowhg)
REVIDX_ELLIPSIS = repository.REVISION_FLAG_ELLIPSIS
# revision data is stored externally
REVIDX_EXTSTORED = repository.REVISION_FLAG_EXTSTORED
# revision data contains extra metadata not part of the official digest
REVIDX_SIDEDATA = repository.REVISION_FLAG_SIDEDATA
REVIDX_DEFAULT_FLAGS = 0
# stable order in which flags need to be processed and their processors applied
REVIDX_FLAGS_ORDER = [
REVIDX_ISCENSORED,
REVIDX_ELLIPSIS,
REVIDX_EXTSTORED,
REVIDX_SIDEDATA,
]
# bitmark for flags that could cause rawdata content change
REVIDX_RAWTEXT_CHANGING_FLAGS = (
REVIDX_ISCENSORED | REVIDX_EXTSTORED | REVIDX_SIDEDATA
)
SPARSE_REVLOG_MAX_CHAIN_LENGTH = 1000