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
test stripping of filelogs where the linkrev doesn't always increase
$ echo '[extensions]' >> $HGRCPATH
$ echo 'strip =' >> $HGRCPATH
$ commit()
> {
> hg up -qC null
> count=1
> for i in "$@"; do
> for f in $i; do
> mkdir -p `dirname $f`
> echo $count > $f
> done
> count=`expr $count + 1`
> done
> hg commit -qAm "$*"
> }
2 1 0 2 0 1 2
$ mkdir files
$ cd files
$ hg init orig
$ cd orig
$ commit '201 210'
$ commit '102 120' '210'
$ commit '021'
$ commit '201' '021 120'
$ commit '012 021' '102 201' '120 210'
$ commit '102 120' '012 210' '021 201'
$ commit '201 210' '021 120' '012 102'
$ cd ..
$ hg clone -q -U -r 4 -r 5 -r 6 orig crossed
$ cd crossed
$ for i in 012 021 102 120 201 210; do
> echo $i
> hg debugindex $i
> echo
> done
012
rev linkrev nodeid p1 p2
0 0 b8e02f643373 000000000000 000000000000
1 1 5d9299349fc0 000000000000 000000000000
2 2 2661d26c6496 000000000000 000000000000
021
rev linkrev nodeid p1 p2
0 0 b8e02f643373 000000000000 000000000000
1 2 5d9299349fc0 000000000000 000000000000
2 1 2661d26c6496 000000000000 000000000000
102
rev linkrev nodeid p1 p2
0 1 b8e02f643373 000000000000 000000000000
1 0 5d9299349fc0 000000000000 000000000000
2 2 2661d26c6496 000000000000 000000000000
120
rev linkrev nodeid p1 p2
0 1 b8e02f643373 000000000000 000000000000
1 2 5d9299349fc0 000000000000 000000000000
2 0 2661d26c6496 000000000000 000000000000
201
rev linkrev nodeid p1 p2
0 2 b8e02f643373 000000000000 000000000000
1 0 5d9299349fc0 000000000000 000000000000
2 1 2661d26c6496 000000000000 000000000000
210
rev linkrev nodeid p1 p2
0 2 b8e02f643373 000000000000 000000000000
1 1 5d9299349fc0 000000000000 000000000000
2 0 2661d26c6496 000000000000 000000000000
$ cd ..
$ for i in 0 1 2; do
> hg clone -q -U --pull crossed $i
> echo "% Trying to strip revision $i"
> hg --cwd $i strip $i
> echo "% Verifying"
> hg --cwd $i verify
> echo
> done
% Trying to strip revision 0
saved backup bundle to $TESTTMP/files/0/.hg/strip-backup/cbb8c2f0a2e3-239800b9-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 12 changes to 6 files
% Trying to strip revision 1
saved backup bundle to $TESTTMP/files/1/.hg/strip-backup/124ecc0cbec9-6104543f-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 12 changes to 6 files
% Trying to strip revision 2
saved backup bundle to $TESTTMP/files/2/.hg/strip-backup/f6439b304a1a-c6505a5f-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 2 changesets with 12 changes to 6 files
$ cd ..
Do a similar test where the manifest revlog has unordered linkrevs
$ mkdir manifests
$ cd manifests
$ hg init orig
$ cd orig
$ commit 'file'
$ commit 'other'
$ commit '' 'other'
$ HGUSER=another-user; export HGUSER
$ commit 'file'
$ commit 'other' 'file'
$ cd ..
$ hg clone -q -U -r 1 -r 2 -r 3 -r 4 orig crossed
$ cd crossed
$ hg debugindex --manifest
rev linkrev nodeid p1 p2
0 2 6bbc6fee55c2 000000000000 000000000000
1 0 1c556153fe54 000000000000 000000000000
2 1 1f76dba919fd 000000000000 000000000000
3 3 bbee06ad59d5 000000000000 000000000000
$ cd ..
$ for i in 2 3; do
> hg clone -q -U --pull crossed $i
> echo "% Trying to strip revision $i"
> hg --cwd $i strip $i
> echo "% Verifying"
> hg --cwd $i verify
> echo
> done
% Trying to strip revision 2
saved backup bundle to $TESTTMP/manifests/2/.hg/strip-backup/f3015ad03c03-4d98bdc2-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 3 changes to 2 files
% Trying to strip revision 3
saved backup bundle to $TESTTMP/manifests/3/.hg/strip-backup/9632aa303aa4-69192e3f-backup.hg
% Verifying
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 3 changes to 2 files
$ cd ..
Now a similar test for a non-root manifest revlog
$ cat >> $HGRCPATH <<EOF
> [experimental]
> treemanifests = yes
> EOF
$ mkdir treemanifests
$ cd treemanifests
$
$ hg --config experimental.treemanifest=True init orig
$ cd orig
$ commit 'dir/file'
$ commit 'dir/other'
$ commit '' 'dir/other'
$ HGUSER=yet-another-user; export HGUSER
$ commit 'otherdir dir/file'
$ commit 'otherdir dir/other' 'otherdir dir/file'
$ cd ..
$ hg --config experimental.treemanifest=True clone -q -U -r 1 -r 2 -r 3 -r 4 orig crossed
$ cd crossed
$ hg debugindex --dir dir
rev linkrev nodeid p1 p2
0 2 6bbc6fee55c2 000000000000 000000000000
1 0 1c556153fe54 000000000000 000000000000
2 1 1f76dba919fd 000000000000 000000000000
3 3 bbee06ad59d5 000000000000 000000000000
$ cd ..
$ for i in 2 3; do
> hg --config experimental.treemanifest=True clone -q -U --pull crossed $i
> echo "% Trying to strip revision $i"
> hg --cwd $i strip $i
> echo "% Verifying"
> hg --cwd $i verify
> echo
> done
% Trying to strip revision 2
saved backup bundle to $TESTTMP/treemanifests/2/.hg/strip-backup/145f5c75f9ac-a105cfbe-backup.hg
% Verifying
checking changesets
checking manifests
checking directory manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 4 changes to 3 files
% Trying to strip revision 3
saved backup bundle to $TESTTMP/treemanifests/3/.hg/strip-backup/e4e3de5c3cb2-f4c70376-backup.hg
% Verifying
checking changesets
checking manifests
checking directory manifests
crosschecking files in changesets and manifests
checking files
checked 3 changesets with 4 changes to 3 files
$ cd ..