upstream/mercurial-mirror Files · mercurial/node.py

nodemap: also use persistent nodemap for manifest...

nodemap: also use persistent nodemap for manifest The manifest as a different usage pattern than the changelog. First, while the lookup in changelog are not garanteed to match, the lookup in the manifest nodemap come from changelog and will exist in the manifest. In addition, looking up a manifest almost always result in unpacking a manifest an operation that rarely come cheap. Nevertheless, using a persistent nodemap provide a significant gain for some operations. For our measurementw, we use `hg cat --rev REV FILE` on the our reference mozilla-try. On this repository the persistent nodemap cache is about 29 MB in side for a total store side of 11,988 MB File with large history (file: b2g/config/gaia.json, revision: 195a1146daa0) no optimisation: 0.358s using mmap for index: 0.297s (-0.061s) persistent nodemap for changelog only: 0.275s (-0.024s) persistent nodemap for manifest too: 0.258s (-0.017s) File with small history (file: .hgignore, revision: 195a1146daa0) no optimisation: 0.377s using mmap for index: 0.296s (-0.061s) persistent nodemap for changelog only: 0.274s (-0.022s) persistent nodemap for manifest too: 0.257s (-0.017s) Same file but using a revision (8ba995b74e18) with a smaller manifest (3944829 bytes vs 10 bytes) no optimisation: 0.192s (-0.185s) using mmap for index: 0.131s (-0.061s) persistent nodemap for changelog only: 0.106s (-0.025s) persistent nodemap for manifest too: 0.087s (-0.019s) Differential Revision: https://phab.mercurial-scm.org/D8410

Augie Fackler - - Load All Authors

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      # node.py - basic nodeid manipulation for mercurial

      #

      # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>

      #

      # This software may be used and distributed according to the terms of the

      # GNU General Public License version 2 or any later version.

      from __future__ import absolute_import

      import binascii

      # This ugly style has a noticeable effect in manifest parsing

      hex = binascii.hexlify

      # Adapt to Python 3 API changes. If this ends up showing up in

      # profiles, we can use this version only on Python 3, and forward

      # binascii.unhexlify like we used to on Python 2.

      def bin(s):

          try:

              return binascii.unhexlify(s)

          except binascii.Error as e:

              raise TypeError(e)

      nullrev = -1

      # In hex, this is '0000000000000000000000000000000000000000'

      nullid = b"\0" * 20

      nullhex = hex(nullid)

      # Phony node value to stand-in for new files in some uses of

      # manifests.

      # In hex, this is '2121212121212121212121212121212121212121'

      newnodeid = b'!!!!!!!!!!!!!!!!!!!!'

      # In hex, this is '3030303030303030303030303030306164646564'

      addednodeid = b'000000000000000added'

      # In hex, this is '3030303030303030303030306d6f646966696564'

      modifiednodeid = b'000000000000modified'

      wdirfilenodeids = {newnodeid, addednodeid, modifiednodeid}

      # pseudo identifiers for working directory

      # (they are experimental, so don't add too many dependencies on them)

      wdirrev = 0x7FFFFFFF

      # In hex, this is 'ffffffffffffffffffffffffffffffffffffffff'

      wdirid = b"\xff" * 20

      wdirhex = hex(wdirid)

      def short(node):

          return hex(node[:6])

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				# node.py - basic nodeid manipulation for mercurial
				#
				# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
				#
				# This software may be used and distributed according to the terms of the
				# GNU General Public License version 2 or any later version.

				from __future__ import absolute_import

				import binascii

				# This ugly style has a noticeable effect in manifest parsing
				hex = binascii.hexlify
				# Adapt to Python 3 API changes. If this ends up showing up in
				# profiles, we can use this version only on Python 3, and forward
				# binascii.unhexlify like we used to on Python 2.
				def bin(s):
				try:
				return binascii.unhexlify(s)
				except binascii.Error as e:
				raise TypeError(e)


				nullrev = -1
				# In hex, this is '0000000000000000000000000000000000000000'
				nullid = b"\0" * 20
				nullhex = hex(nullid)

				# Phony node value to stand-in for new files in some uses of
				# manifests.
				# In hex, this is '2121212121212121212121212121212121212121'
				newnodeid = b'!!!!!!!!!!!!!!!!!!!!'
				# In hex, this is '3030303030303030303030303030306164646564'
				addednodeid = b'000000000000000added'
				# In hex, this is '3030303030303030303030306d6f646966696564'
				modifiednodeid = b'000000000000modified'

				wdirfilenodeids = {newnodeid, addednodeid, modifiednodeid}

				# pseudo identifiers for working directory
				# (they are experimental, so don't add too many dependencies on them)
				wdirrev = 0x7FFFFFFF
				# In hex, this is 'ffffffffffffffffffffffffffffffffffffffff'
				wdirid = b"\xff" * 20
				wdirhex = hex(wdirid)


				def short(node):
				return hex(node[:6])