view tests/test-debug-revlog-stats.t @ 51181:dcaa2df1f688

changelog: never inline changelog

The test suite mostly use small repositories, that implies that most changelog in the
tests are inlined. As a result, non-inlined changelog are quite poorly tested.
Since non-inline changelog are most common case for serious repositories, this
lack of testing is a significant problem that results in high profile issue like
the one recently fixed by 66417f55ea33 and 849745d7da89.

Inlining the changelog does not bring much to the table, the number of total
file saved is negligible, and the changelog will be read by most operation
anyway.

So this changeset is make it so we never inline the changelog, and de-inline the
one that are still inlined whenever we touch them.

By doing that, we remove the "dual code path" situation for writing new entry to
the changelog and move to a "single code path" situation. Having a single
code path simplify the code and make sure it is covered by test (if test cover
that situation obviously)


This impact all tests that care about the number of file and the exchange size,
but there is nothing too complicated in them just a lot of churn.

The churn is made "worse" by the fact rust will use the persistent nodemap on
any changelog now. Which is overall a win as it means testing the persistent
nodemap more and having less special cases.

In short, having inline changelog is mostly useless and an endless source of
pain. We get rid of it.

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 !)