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

diff: do not concatenate immutable bytes while building a/b bodies (issue6445)...

diff: do not concatenate immutable bytes while building a/b bodies (issue6445) Use bytearray instead. I don't know what's changed since Python 2, but bytes concatenation is 100x slow on Python 3. % python2.7 -m timeit -s "s = b''" "for i in range(10000): s += b'line'" 1000 loops, best of 3: 321 usec per loop % python3.9 -m timeit -s "s = b''" "for i in range(10000): s += b'line'" 5 loops, best of 5: 39.2 msec per loop Benchmark using tailwind.css (measuring the fast path, a is empty): % HGRCPATH=/dev/null python2.7 ./hg log -R /tmp/issue6445 -p --time \ --color=always --config diff.word-diff=true >/dev/null (prev) time: real 1.580 secs (user 1.560+0.000 sys 0.020+0.000) (this) time: real 1.610 secs (user 1.570+0.000 sys 0.030+0.000) % HGRCPATH=/dev/null python3.9 ./hg log -R /tmp/issue6445 -p --time \ --color=always --config diff.word-diff=true >/dev/null (prev) time: real 114.500 secs (user 114.460+0.000 sys 0.030+0.000) (this) time: real 2.180 secs (user 2.140+0.000 sys 0.040+0.000) Benchmark using random tabular text data (not the fast path): % dd if=/dev/urandom bs=1k count=1000 | hexdump -v -e '16/1 "%3u," "\n"' > ttf % hg ci -ma % dd if=/dev/urandom bs=1k count=1000 | hexdump -v -e '16/1 "%3u," "\n"' > ttf % hg ci -mb % HGRCPATH=/dev/null python2.7 ./hg log -R /tmp/issue6445 -p --time \ --color=always --config diff.word-diff=true >/dev/null (prev) time: real 3.240 secs (user 3.040+0.000 sys 0.200+0.000 (this) time: real 3.230 secs (user 3.070+0.000 sys 0.160+0.000) % HGRCPATH=/dev/null python3.9 ./hg log -R /tmp/issue6445 -p --time \ --color=always --config diff.word-diff=true >/dev/null (prev) time: real 44.130 secs (user 43.850+0.000 sys 0.270+0.000) (this) time: real 4.170 secs (user 3.850+0.000 sys 0.310+0.000)

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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])