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Differential D9674

engine: refactor code to replace stores in separate function
ClosedPublic

Authored by pulkit on Dec 31 2020, 11:42 AM.

Details

Reviewers
marmoute
Group Reviewers
hg-reviewers
Commits
rHG1ca7865c245d: engine: refactor code to replace stores in separate function
Summary

In not all upgrades, we need to change the whole store. For example, when
upgrading repository to share-safe mode, we don't touch revlogs at all hence
store cloning and copying is not required.

The store replacing code needs to be made aware about what all has changed and
hence only copy/rename those things. To kickstart that, this patch moves
existing logic into a separate function.

Diff Detail

Repository
rHG Mercurial
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default
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Event Timeline

pulkit created this revision.Dec 31 2020, 11:42 AM
marmoute accepted this revision.Jan 7 2021, 9:40 PM
pulkit added a commit: rHG1ca7865c245d: engine: refactor code to replace stores in separate function.Jan 12 2021, 8:54 PM
This revision was not accepted when it landed; it landed in state Needs Review.
Closed by commit rHG1ca7865c245d: engine: refactor code to replace stores in separate function (authored by pulkit). · Explain Why
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/upgrade_utils/engine.py (22 lines)

Diff 24561

mercurial/upgrade_utils/engine.py

# Skip other skipped files. # Skip other skipped files.
if path in (b'lock', b'fncache'): if path in (b'lock', b'fncache'):
continue continue
# TODO: should we skip cache too? # TODO: should we skip cache too?
yield path yield path
def _replacestores(currentrepo, upgradedrepo, backupvfs, upgrade_op):
"""Replace the stores after current repository is upgraded
Creates a backup of current repository store at backup path
Replaces upgraded store files in current repo from upgraded one
Arguments:
currentrepo: repo object of current repository
upgradedrepo: repo object of the upgraded data
backupvfs: vfs object for the backup path
upgrade_op: upgrade operation object
to be used to decide what all is upgraded
"""
# TODO: don't blindly rename everything in store
# There can be upgrades where store is not touched at all
util.rename(currentrepo.spath, backupvfs.join(b'store'))
util.rename(upgradedrepo.spath, currentrepo.spath)
def finishdatamigration(ui, srcrepo, dstrepo, requirements): def finishdatamigration(ui, srcrepo, dstrepo, requirements):
"""Hook point for extensions to perform additional actions during upgrade. """Hook point for extensions to perform additional actions during upgrade.
This function is called after revlogs and store files have been copied but This function is called after revlogs and store files have been copied but
before the new store is swapped into the original location. before the new store is swapped into the original location.
""" """
ui.status(_(b'starting in-place swap of repository data\n')) ui.status(_(b'starting in-place swap of repository data\n'))
ui.status(_(b'replaced files will be backed up at %s\n') % backuppath) ui.status(_(b'replaced files will be backed up at %s\n') % backuppath)
# Now swap in the new store directory. Doing it as a rename should make # Now swap in the new store directory. Doing it as a rename should make
# the operation nearly instantaneous and atomic (at least in well-behaved # the operation nearly instantaneous and atomic (at least in well-behaved
# environments). # environments).
ui.status(_(b'replacing store...\n')) ui.status(_(b'replacing store...\n'))
tstart = util.timer() tstart = util.timer()
util.rename(srcrepo.spath, backupvfs.join(b'store')) _replacestores(srcrepo, dstrepo, backupvfs, upgrade_op)
util.rename(dstrepo.spath, srcrepo.spath)
elapsed = util.timer() - tstart elapsed = util.timer() - tstart
ui.status( ui.status(
_( _(
b'store replacement complete; repository was inconsistent for ' b'store replacement complete; repository was inconsistent for '
b'%0.1fs\n' b'%0.1fs\n'
) )
% elapsed % elapsed
) )