tags-cache: directly perform a monimal walk for hgtagsfnodescache warming
We do something narrower than the path retrieving data. So lets use dedicated
code instead.
This provides further useful speedup:
### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
# benchmark.name = hg.debug.debug-update-cache
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.pre-state = warm
before-this-series: 19.947581
skip-fnode-filter: 18.916804 (-5.17%, -1.03)
use-rev-num: 17.493725 (-12.30%, -2.45)
this-changesets: 15.919466 (-20.19%, -4.03)
Force revlog max inline value to be smaller than default
$ mkdir $TESTTMP/ext
$ cat << EOF > $TESTTMP/ext/small_inline.py
> from mercurial import revlog
> revlog._maxinline = 8
> EOF
$ cat << EOF >> $HGRCPATH
> [extensions]
> small_inline=$TESTTMP/ext/small_inline.py
> EOF
$ hg init repo
$ cd repo
Try on an empty repository
$ hg debug-revlog-stats
rev-count data-size inl type target
$ mkdir folder
$ touch a b folder/c folder/d
$ hg commit -Aqm 0
$ echo "text" > a
$ hg rm b
$ echo "longer string" > folder/d
$ hg commit -Aqm 1
Differences in data size observed with pure is due to different compression
algorithms
$ hg debug-revlog-stats
rev-count data-size inl type target
2 138 no changelog (no-pure !)
2 137 no changelog (pure !)
2 177 no manifest (no-pure !)
2 168 no manifest (pure !)
2 6 yes file a
1 0 yes file b
1 0 yes file folder/c
2 15 no file folder/d
Test 'changelog' command argument
$ hg debug-revlog-stats -c
rev-count data-size inl type target
2 138 no changelog (no-pure !)
2 137 no changelog (pure !)
Test 'manifest' command argument
$ hg debug-revlog-stats -m
rev-count data-size inl type target
2 177 no manifest (no-pure !)
2 168 no manifest (pure !)
Test 'file' command argument
$ hg debug-revlog-stats -f
rev-count data-size inl type target
2 6 yes file a
1 0 yes file b
1 0 yes file folder/c
2 15 no file folder/d
Test multiple command arguments
$ hg debug-revlog-stats -cm
rev-count data-size inl type target
2 138 no changelog (no-pure !)
2 137 no changelog (pure !)
2 177 no manifest (no-pure !)
2 168 no manifest (pure !)