( )⚙ D10631 revlogv2: track pending write in the docket and expose it to hooks

This is an archive of the discontinued Mercurial Phabricator instance.

Differential D10631

revlogv2: track pending write in the docket and expose it to hooks
ClosedPublic

Authored by marmoute on May 3 2021, 7:55 AM.

Details

Reviewers
indygreg
Alphare
Group Reviewers
hg-reviewers
Commits
rHG2219853a1503: revlogv2: track pending write in the docket and expose it to hooks
Summary

The docket is now able to write pending data. We could have used a distinct
intermediate files, however keeping everything in the same file will make it
simpler to keep track of the various involved files if necessary.

However it might prove more complicated for streaming clone. This will be dealt
with later.

Note that we lifted the stderr redirection in the test since we no longer suffer
from "unkown working directory parent" message.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

marmoute created this revision.May 3 2021, 7:55 AM
baymax updated this revision to Diff 27474.May 3 2021, 9:32 PM

✅ refresh by Heptapod after a successful CI run (🐙 💚)

marmoute updated this revision to Diff 27546.May 4 2021, 10:13 AM
baymax updated this revision to Diff 27877.May 11 2021, 1:44 PM

✅ refresh by Heptapod after a successful CI run (🐙 💚)

Alphare accepted this revision.May 17 2021, 5:48 PM
This revision is now accepted and ready to land.May 17 2021, 5:48 PM

Revision Contents
Changeset List

Diff 28031

mercurial/changelog.py

The ``00changelog.i.a`` file contains index (and possibly inline The ``00changelog.i.a`` file contains index (and possibly inline
revision) data for a transaction that hasn't been finalized yet. revision) data for a transaction that hasn't been finalized yet.
It exists in a separate file to facilitate readers (such as It exists in a separate file to facilitate readers (such as
hooks processes) accessing data before a transaction is finalized. hooks processes) accessing data before a transaction is finalized.
``concurrencychecker`` will be passed to the revlog init function, see ``concurrencychecker`` will be passed to the revlog init function, see
the documentation there. the documentation there.
""" """
revlog.revlog.__init__( revlog.revlog.__init__(
self, self,
opener, opener,
target=(revlog_constants.KIND_CHANGELOG, None), target=(revlog_constants.KIND_CHANGELOG, None),
radix=b'00changelog', radix=b'00changelog',
checkambig=True, checkambig=True,
mmaplargeindex=True, mmaplargeindex=True,
persistentnodemap=opener.options.get(b'persistent-nodemap', False), persistentnodemap=opener.options.get(b'persistent-nodemap', False),
self._delaybuf = None self._delaybuf = None
self._divert = False self._divert = False
# split when we're done # split when we're done
self._enforceinlinesize(tr) self._enforceinlinesize(tr)
def _writepending(self, tr): def _writepending(self, tr):
"""create a file containing the unfinalized state for """create a file containing the unfinalized state for
pretxnchangegroup""" pretxnchangegroup"""
if self._docket:
return self._docket.write(tr, pending=True)
if self._delaybuf: if self._delaybuf:
# make a temporary copy of the index # make a temporary copy of the index
fp1 = self._realopener(self._indexfile) fp1 = self._realopener(self._indexfile)
pendingfilename = self._indexfile + b".a" pendingfilename = self._indexfile + b".a"
# register as a temp file to ensure cleanup on failure # register as a temp file to ensure cleanup on failure
tr.registertmp(pendingfilename) tr.registertmp(pendingfilename)
# write existing data # write existing data
fp2 = self._realopener(pendingfilename, b"w") fp2 = self._realopener(pendingfilename, b"w")

mercurial/configitems.py

) )
coreconfigitem( coreconfigitem(
b'experimental', b'experimental',
b'revisions.prefixhexnode', b'revisions.prefixhexnode',
default=False, default=False,
) )
# "out of experimental" todo list. # "out of experimental" todo list.
# #
# * expose transaction content hooks during pre-commit validation
# * include management of a persistent nodemap in the main docket # * include management of a persistent nodemap in the main docket
# * enforce a "no-truncate" policy for mmap safety # * enforce a "no-truncate" policy for mmap safety
# - for censoring operation # - for censoring operation
# - for stripping operation # - for stripping operation
# - for rollback operation # - for rollback operation
# * proper streaming (race free) of the docket file # * proper streaming (race free) of the docket file
# * store the data size in the docket to simplify sidedata rewrite. # * store the data size in the docket to simplify sidedata rewrite.
# * track garbage data to evemtually allow rewriting -existing- sidedata. # * track garbage data to evemtually allow rewriting -existing- sidedata.

mercurial/revlog.py

if not features[b'docket']: if not features[b'docket']:
self._indexfile = entry_point self._indexfile = entry_point
index_data = entry_data index_data = entry_data
else: else:
self._docket_file = entry_point self._docket_file = entry_point
if self._initempty: if self._initempty:
self._docket = docketutil.default_docket(self, header) self._docket = docketutil.default_docket(self, header)
else: else:
self._docket = docketutil.parse_docket(self, entry_data) self._docket = docketutil.parse_docket(
self, entry_data, use_pending=self._trypending
)
self._indexfile = self._docket.index_filepath() self._indexfile = self._docket.index_filepath()
index_data = b'' index_data = b''
index_size = self._docket.index_end index_size = self._docket.index_end
if index_size > 0: if index_size > 0:
index_data = self._get_data( index_data = self._get_data(
self._indexfile, mmapindexthreshold, size=index_size self._indexfile, mmapindexthreshold, size=index_size
) )
if len(index_data) < index_size: if len(index_data) < index_size:

mercurial/revlogutils/docket.py

# * an index file, containing fixed width information about revisions, # * an index file, containing fixed width information about revisions,
# #
# * a data file, containing variable width data for these revisions, # * a data file, containing variable width data for these revisions,
from __future__ import absolute_import from __future__ import absolute_import
import struct import struct
from .. import (
error,
)
from . import ( from . import (
constants, constants,
) )
# Docket format # Docket format
# #
# * 4 bytes: revlog version # * 4 bytes: revlog version
# | This is mandatory as docket must be compatible with the previous # | This is mandatory as docket must be compatible with the previous
# | revlog index header. # | revlog index header.
# * 8 bytes: size of index data # * 8 bytes: size of index data
S_HEADER = struct.Struct(constants.INDEX_HEADER.format + 'L') # * 8 bytes: pending size of index data
S_HEADER = struct.Struct(constants.INDEX_HEADER.format + 'LL')
class RevlogDocket(object): class RevlogDocket(object):
"""metadata associated with revlog""" """metadata associated with revlog"""
def __init__(self, revlog, version_header=None, index_end=0): def __init__(
self,
revlog,
use_pending=False,
version_header=None,
index_end=0,
pending_index_end=0,
):
self._version_header = version_header self._version_header = version_header
self._read_only = bool(use_pending)
self._dirty = False self._dirty = False
self._radix = revlog.radix self._radix = revlog.radix
self._path = revlog._docket_file self._path = revlog._docket_file
self._opener = revlog.opener self._opener = revlog.opener
self._index_end = index_end # this assert should be True as long as we have a single index filename
assert index_end <= pending_index_end
self._initial_index_end = index_end
self._pending_index_end = pending_index_end
if use_pending:
self._index_end = self._pending_index_end
else:
self._index_end = self._initial_index_end
def index_filepath(self): def index_filepath(self):
"""file path to the current index file associated to this docket""" """file path to the current index file associated to this docket"""
# very simplistic version at first # very simplistic version at first
return b"%s.idx" % self._radix return b"%s.idx" % self._radix
@property @property
def index_end(self): def index_end(self):
return self._index_end return self._index_end
@index_end.setter @index_end.setter
def index_end(self, new_size): def index_end(self, new_size):
if new_size != self._index_end: if new_size != self._index_end:
self._index_end = new_size self._index_end = new_size
self._dirty = True self._dirty = True
def write(self, transaction, stripping=False): def write(self, transaction, pending=False, stripping=False):
"""write the modification of disk if any """write the modification of disk if any
This make the new content visible to all process""" This make the new content visible to all process"""
if self._dirty: if not self._dirty:
return False
else:
if self._read_only:
msg = b'writing read-only docket: %s'
msg %= self._path
raise error.ProgrammingError(msg)
if not stripping: if not stripping:
# XXX we could, leverage the docket while stripping. However it # XXX we could, leverage the docket while stripping. However it
# is not powerfull enough at the time of this comment # is not powerfull enough at the time of this comment
transaction.addbackup(self._path, location=b'store') transaction.addbackup(self._path, location=b'store')
with self._opener(self._path, mode=b'w', atomictemp=True) as f: with self._opener(self._path, mode=b'w', atomictemp=True) as f:
f.write(self._serialize()) f.write(self._serialize(pending=pending))
self._dirty = False # if pending we still need to the write final data eventually
self._dirty = pending
return True
def _serialize(self, pending=False):
if pending:
official_index_end = self._initial_index_end
else:
official_index_end = self._index_end
def _serialize(self): # this assert should be True as long as we have a single index filename
assert official_index_end <= self._index_end
data = ( data = (
self._version_header, self._version_header,
official_index_end,
self._index_end, self._index_end,
) )
return S_HEADER.pack(*data) return S_HEADER.pack(*data)
def default_docket(revlog, version_header): def default_docket(revlog, version_header):
"""given a revlog version a new docket object for the given revlog""" """given a revlog version a new docket object for the given revlog"""
if (version_header & 0xFFFF) != constants.REVLOGV2: if (version_header & 0xFFFF) != constants.REVLOGV2:
return None return None
docket = RevlogDocket(revlog, version_header=version_header) docket = RevlogDocket(revlog, version_header=version_header)
docket._dirty = True docket._dirty = True
return docket return docket
def parse_docket(revlog, data): def parse_docket(revlog, data, use_pending=False):
"""given some docket data return a docket object for the given revlog""" """given some docket data return a docket object for the given revlog"""
header = S_HEADER.unpack(data[: S_HEADER.size]) header = S_HEADER.unpack(data[: S_HEADER.size])
version_header, index_size = header version_header, index_size, pending_index_size = header
docket = RevlogDocket( docket = RevlogDocket(
revlog, revlog,
use_pending=use_pending,
version_header=version_header, version_header=version_header,
index_end=index_size, index_end=index_size,
pending_index_end=pending_index_size,
) )
return docket return docket

tests/test-transaction-safety.t

$ export HG_TEST_FILE_EXT_WAITING $ export HG_TEST_FILE_EXT_WAITING
$ HG_TEST_FILE_EXT_UNLOCK=$TESTTMP/sync/ext_unlock $ HG_TEST_FILE_EXT_UNLOCK=$TESTTMP/sync/ext_unlock
$ export HG_TEST_FILE_EXT_UNLOCK $ export HG_TEST_FILE_EXT_UNLOCK
$ HG_TEST_FILE_EXT_DONE=$TESTTMP/sync/ext_done $ HG_TEST_FILE_EXT_DONE=$TESTTMP/sync/ext_done
$ export HG_TEST_FILE_EXT_DONE $ export HG_TEST_FILE_EXT_DONE
$ cat << EOF > script/external.sh $ cat << EOF > script/external.sh
> #!/bin/sh > #!/bin/sh
> $RUNTESTDIR/testlib/wait-on-file 5 $HG_TEST_FILE_EXT_UNLOCK $HG_TEST_FILE_EXT_WAITING > $RUNTESTDIR/testlib/wait-on-file 5 $HG_TEST_FILE_EXT_UNLOCK $HG_TEST_FILE_EXT_WAITING
> hg log --rev 'tip' -T 'external: {rev} {desc}\n' > $TESTTMP/output/external.out 2>/dev/null > hg log --rev 'tip' -T 'external: {rev} {desc}\n' > $TESTTMP/output/external.out
> touch $HG_TEST_FILE_EXT_DONE > touch $HG_TEST_FILE_EXT_DONE
> EOF > EOF
$ chmod +x script/external.sh $ chmod +x script/external.sh
$ cat << EOF > script/internal.sh $ cat << EOF > script/internal.sh
> #!/bin/sh > #!/bin/sh
> hg log --rev 'tip' -T 'internal: {rev} {desc}\n' > $TESTTMP/output/internal.out 2>/dev/null > hg log --rev 'tip' -T 'internal: {rev} {desc}\n' > $TESTTMP/output/internal.out
> $RUNTESTDIR/testlib/wait-on-file 5 $HG_TEST_FILE_EXT_DONE $HG_TEST_FILE_EXT_UNLOCK > $RUNTESTDIR/testlib/wait-on-file 5 $HG_TEST_FILE_EXT_DONE $HG_TEST_FILE_EXT_UNLOCK
> EOF > EOF
$ chmod +x script/internal.sh $ chmod +x script/internal.sh
Automated commands: Automated commands:
$ make_one_commit() { $ make_one_commit() {
check this is true for the initial commit (inline → inline) check this is true for the initial commit (inline → inline)
----------------------------------------------------------- -----------------------------------------------------------
the repository should still be inline (for relevant format) the repository should still be inline (for relevant format)
$ make_one_commit first $ make_one_commit first
pre-commit: -1 pre-commit: -1
external: -1 external: -1
internal: 0 first (revlogv1 !) internal: 0 first
internal: -1 (revlogv2 known-bad-output !)
post-tr: 0 first post-tr: 0 first
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
flags : inline flags : inline
#endif #endif
check this is true for extra commit (inline → inline) check this is true for extra commit (inline → inline)
----------------------------------------------------- -----------------------------------------------------
the repository should still be inline (for relevant format) the repository should still be inline (for relevant format)
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
flags : inline flags : inline
#endif #endif
$ make_one_commit second $ make_one_commit second
pre-commit: 0 first pre-commit: 0 first
external: 0 first external: 0 first
internal: 1 second (revlogv1 !) internal: 1 second
internal: 0 first (revlogv2 known-bad-output !)
post-tr: 1 second post-tr: 1 second
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
flags : inline flags : inline
#endif #endif
flags : inline flags : inline
#endif #endif
$ make_one_pull 3 $ make_one_pull 3
pre-commit: 1 second pre-commit: 1 second
warning: repository is unrelated warning: repository is unrelated
external: 1 second external: 1 second
internal: 5 r3 (revlogv1 !) internal: 5 r3
internal: 1 second (revlogv2 known-bad-output !)
post-tr: 5 r3 post-tr: 5 r3
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
flags : inline flags : inline
#endif #endif
Make a large pull (inline → no-inline) Make a large pull (inline → no-inline)
--------------------------------------- ---------------------------------------
the repository should no longer be inline (for relevant format) the repository should no longer be inline (for relevant format)
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
flags : inline flags : inline
#endif #endif
$ make_one_pull 400 $ make_one_pull 400
pre-commit: 5 r3 pre-commit: 5 r3
external: 5 r3 external: 5 r3
internal: 402 r400 (revlogv1 !) internal: 402 r400
internal: 5 r3 (revlogv2 known-bad-output !)
post-tr: 402 r400 post-tr: 402 r400
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
[1] [1]
#endif #endif
check this is true for extra commit (no-inline → no-inline) check this is true for extra commit (no-inline → no-inline)
----------------------------------------------------------- -----------------------------------------------------------
the repository should no longer be inline (for relevant format) the repository should no longer be inline (for relevant format)
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
[1] [1]
#endif #endif
$ make_one_commit third $ make_one_commit third
pre-commit: 402 r400 pre-commit: 402 r400
external: 402 r400 external: 402 r400
internal: 403 third (revlogv1 !) internal: 403 third
internal: 402 r400 (revlogv2 known-bad-output !)
post-tr: 403 third post-tr: 403 third
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
[1] [1]
#endif #endif
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
[1] [1]
#endif #endif
$ make_one_pull tip $ make_one_pull tip
pre-commit: 403 third pre-commit: 403 third
external: 403 third external: 403 third
internal: 503 r500 (revlogv1 !) internal: 503 r500
internal: 403 third (revlogv2 known-bad-output !)
post-tr: 503 r500 post-tr: 503 r500
#if revlogv1 #if revlogv1
$ hg debugrevlog -c | grep inline $ hg debugrevlog -c | grep inline
[1] [1]
#endif #endif