rust-nodemap: accounting for dead blocks
By the very append-only nature of the `NodeTree`, inserting
new blocks has the effect of making some of the older ones
useless as they become unreachable.
Therefore some automatic housekeeping will need to be provided.
This is standard procedure in the word of databases, under names
such as "repack" or "vacuum".
The new `masked_readonly_blocks()` will provide callers with
useful information to decide if the nodetree is ripe for
repacking, but all the `NodeTree` can provide is how many
blocks have been masked in the currently mutable part. Analysing
the readonly part would be way too long to do it for each
transaction and defeat the whole purpose of nodemap persistence.
Serializing callers (from the Python layer) will get this figure
before each extraction and maintain an aggregate counter of
unreachable blocks separately.
Note: at this point, the most efficient repacking is just to restart
afresh with a full rescan.
Differential Revision: https://phab.mercurial-scm.org/D8097
# Create server
$ hg init server
$ cd server
$ cat >> .hg/hgrc << EOF
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> EOF
$ cd ../
# Clone server and enable extensions
$ hg clone -q server client
$ cd client
$ cat >> .hg/hgrc << EOF
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> EOF
# Commit file that will trigger the noop extension
$ echo '[NOOP]' > noop
$ hg commit -Aqm "noop"
# Commit file that will trigger the base64 extension
$ echo '[BASE64]' > base64
$ hg commit -Aqm 'base64'
# Commit file that will trigger the gzip extension
$ echo '[GZIP]' > gzip
$ hg commit -Aqm 'gzip'
# Commit file that will trigger noop and base64
$ echo '[NOOP][BASE64]' > noop-base64
$ hg commit -Aqm 'noop+base64'
# Commit file that will trigger noop and gzip
$ echo '[NOOP][GZIP]' > noop-gzip
$ hg commit -Aqm 'noop+gzip'
# Commit file that will trigger base64 and gzip
$ echo '[BASE64][GZIP]' > base64-gzip
$ hg commit -Aqm 'base64+gzip'
# Commit file that will trigger base64, gzip and noop
$ echo '[BASE64][GZIP][NOOP]' > base64-gzip-noop
$ hg commit -Aqm 'base64+gzip+noop'
# TEST: ensure the revision data is consistent
$ hg cat noop
[NOOP]
$ hg debugdata noop 0
[NOOP]
$ hg cat -r . base64
[BASE64]
$ hg debugdata base64 0
W0JBU0U2NF0K (no-eol)
$ hg cat -r . gzip
[GZIP]
$ hg debugdata gzip 0
x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)
$ hg cat -r . noop-base64
[NOOP][BASE64]
$ hg debugdata noop-base64 0
W05PT1BdW0JBU0U2NF0K (no-eol)
$ hg cat -r . noop-gzip
[NOOP][GZIP]
$ hg debugdata noop-gzip 0
x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)
$ hg cat -r . base64-gzip
[BASE64][GZIP]
$ hg debugdata base64-gzip 0
eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)
$ hg cat -r . base64-gzip-noop
[BASE64][GZIP][NOOP]
$ hg debugdata base64-gzip-noop 0
eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)
# Push to the server
$ hg push
pushing to $TESTTMP/server
searching for changes
adding changesets
adding manifests
adding file changes
added 7 changesets with 7 changes to 7 files
Ensure the data got to the server OK
$ cd ../server
$ hg cat -r 6e48f4215d24 noop
[NOOP]
$ hg debugdata noop 0
[NOOP]
$ hg cat -r 6e48f4215d24 base64
[BASE64]
$ hg debugdata base64 0
W0JBU0U2NF0K (no-eol)
$ hg cat -r 6e48f4215d24 gzip
[GZIP]
$ hg debugdata gzip 0
x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)
$ hg cat -r 6e48f4215d24 noop-base64
[NOOP][BASE64]
$ hg debugdata noop-base64 0
W05PT1BdW0JBU0U2NF0K (no-eol)
$ hg cat -r 6e48f4215d24 noop-gzip
[NOOP][GZIP]
$ hg debugdata noop-gzip 0
x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)
$ hg cat -r 6e48f4215d24 base64-gzip
[BASE64][GZIP]
$ hg debugdata base64-gzip 0
eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)
$ hg cat -r 6e48f4215d24 base64-gzip-noop
[BASE64][GZIP][NOOP]
$ hg debugdata base64-gzip-noop 0
eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)
# Initialize new client (not cloning) and setup extension
$ cd ..
$ hg init client2
$ cd client2
$ cat >> .hg/hgrc << EOF
> [paths]
> default = $TESTTMP/server
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> EOF
# Pull from server and update to latest revision
$ hg pull default
pulling from $TESTTMP/server
requesting all changes
adding changesets
adding manifests
adding file changes
added 7 changesets with 7 changes to 7 files
new changesets 07b1b9442c5b:6e48f4215d24
(run 'hg update' to get a working copy)
$ hg update
7 files updated, 0 files merged, 0 files removed, 0 files unresolved
# TEST: ensure the revision data is consistent
$ hg cat noop
[NOOP]
$ hg debugdata noop 0
[NOOP]
$ hg cat -r . base64
[BASE64]
$ hg debugdata base64 0
W0JBU0U2NF0K (no-eol)
$ hg cat -r . gzip
[GZIP]
$ hg debugdata gzip 0
x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)
$ hg cat -r . noop-base64
[NOOP][BASE64]
$ hg debugdata noop-base64 0
W05PT1BdW0JBU0U2NF0K (no-eol)
$ hg cat -r . noop-gzip
[NOOP][GZIP]
$ hg debugdata noop-gzip 0
x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)
$ hg cat -r . base64-gzip
[BASE64][GZIP]
$ hg debugdata base64-gzip 0
eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)
$ hg cat -r . base64-gzip-noop
[BASE64][GZIP][NOOP]
$ hg debugdata base64-gzip-noop 0
eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)
# TEST: ensure a missing processor is handled
$ echo '[FAIL][BASE64][GZIP][NOOP]' > fail-base64-gzip-noop
$ hg commit -Aqm 'fail+base64+gzip+noop'
abort: missing processor for flag '0x1'!
[255]
$ rm fail-base64-gzip-noop
# TEST: ensure we cannot register several flag processors on the same flag
$ cat >> .hg/hgrc << EOF
> [extensions]
> extension=$TESTDIR/flagprocessorext.py
> duplicate=$TESTDIR/flagprocessorext.py
> EOF
$ hg debugrebuilddirstate
Traceback (most recent call last):
File "*/mercurial/extensions.py", line *, in _runextsetup (glob)
extsetup(ui)
File "*/tests/flagprocessorext.py", line *, in extsetup (glob)
flagutil.addflagprocessor( (py38 !)
REVIDX_NOOP, (noopdonothingread, noopdonothing, validatehash,) (no-py38 !)
File "*/mercurial/revlogutils/flagutil.py", line *, in addflagprocessor (glob)
insertflagprocessor(flag, processor, flagprocessors)
File "*/mercurial/revlogutils/flagutil.py", line *, in insertflagprocessor (glob)
raise error.Abort(msg)
mercurial.error.Abort: cannot register multiple processors on flag '0x8'. (py3 !)
Abort: cannot register multiple processors on flag '0x8'. (no-py3 !)
*** failed to set up extension duplicate: cannot register multiple processors on flag '0x8'.
$ hg st 2>&1 | egrep 'cannot register multiple processors|flagprocessorext'
File "*/tests/flagprocessorext.py", line *, in extsetup (glob)
mercurial.error.Abort: cannot register multiple processors on flag '0x8'. (py3 !)
Abort: cannot register multiple processors on flag '0x8'. (no-py3 !)
*** failed to set up extension duplicate: cannot register multiple processors on flag '0x8'.
File "*/tests/flagprocessorext.py", line *, in b64decode (glob)
$ cd ..
# TEST: bundle repo
$ hg init bundletest
$ cd bundletest
$ cat >> .hg/hgrc << EOF
> [extensions]
> flagprocessor=$TESTDIR/flagprocessorext.py
> EOF
$ for i in 0 single two three 4; do
> echo '[BASE64]a-bit-longer-'$i > base64
> hg commit -m base64-$i -A base64
> done
$ hg update 2 -q
$ echo '[BASE64]a-bit-longer-branching' > base64
$ hg commit -q -m branching
#if repobundlerepo
$ hg bundle --base 1 bundle.hg
4 changesets found
$ hg --config extensions.strip= strip -r 2 --no-backup --force -q
$ hg -R bundle.hg log --stat -T '{rev} {desc}\n' base64
5 branching
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
4 base64-4
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
3 base64-three
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
2 base64-two
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
1 base64-single
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
0 base64-0
base64 | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
$ hg bundle -R bundle.hg --base 1 bundle-again.hg -q
$ hg -R bundle-again.hg log --stat -T '{rev} {desc}\n' base64
5 branching
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
4 base64-4
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
3 base64-three
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
2 base64-two
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
1 base64-single
base64 | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
0 base64-0
base64 | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
$ rm bundle.hg bundle-again.hg
#endif
# TEST: hg status
$ hg status
$ hg diff