D7492: localrepo: also fastpath access to working copy parents when possible

[marmoute (Pierre-Yves David)]

marmoute added a comment.


  Here is raw perf comparison for status, diff and export. We don't have a benchmark for annottate yet. (not too long to write, but I did not had the time to do that yet)
  
    All benchmarks:
    
           before           after         ratio
         [8e095512]       [36b2f659]
    -       711±0.8ms       60.7±0.2ms     0.09  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -       712±0.8ms       61.6±0.2ms     0.09  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -         690±1ms       93.5±0.3ms     0.14  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -         688±1ms       93.8±0.3ms     0.14  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -         714±1ms       60.7±0.8ms     0.09  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -         713±1ms       60.9±0.3ms     0.09  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -         689±1ms       93.7±0.2ms     0.14  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -         687±2ms       92.8±0.2ms     0.14  simple_command.read.diff.empty.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -         799±2ms       98.1±0.6ms     0.12  simple_command.read.export.bare.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -       800±0.8ms      100.0±0.4ms     0.12  simple_command.read.export.bare.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -       711±0.9ms        111±0.2ms     0.16  simple_command.read.export.bare.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -         711±1ms        112±0.3ms     0.16  simple_command.read.export.bare.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -         760±1ms       59.8±0.1ms     0.08  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -         763±2ms       62.2±0.3ms     0.08  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -         689±1ms       93.1±0.3ms     0.14  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -         688±1ms       94.3±0.3ms     0.14  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 1) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -         763±1ms       60.1±0.2ms     0.08  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -         763±1ms       62.1±0.4ms     0.08  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py2.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]
    -       689±0.8ms       93.2±0.2ms     0.14  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYc-HGWITHRUSTEXTcpython]
    -       687±0.9ms       94.1±0.3ms     0.14  simple_command.read.status.wc_clean.default.time_bench('mercurial-filtered-2019-11-22', 'zstd', 'default', True, True, True, True, True, 2) [citrea/virtualenv-py3.7-pyyaml-HGMODULEPOLICYrust+c-HGWITHRUSTEXTcpython]

REPOSITORY
  rHG Mercurial

CHANGES SINCE LAST ACTION
  https://phab.mercurial-scm.org/D7492/new/

REVISION DETAIL
  https://phab.mercurial-scm.org/D7492

To: marmoute, #hg-reviewers
Cc: pulkit, martinvonz, mercurial-devel