view tests/test-merge-force.t @ 51681:522b4d729e89

mmap: populate the mapping by default

Without pre-population, accessing all data through a mmap can result in many
pagefault, reducing performance significantly. If the mmap is prepopulated, the
performance can no longer get slower than a full read.
(See benchmark number below)

In some cases were very few data is read, prepopulating can be overkill and
slower than populating on access (through page fault). So that behavior can be
controlled when the caller can pre-determine the best behavior.
(See benchmark number below)

In addition, testing with populating in a secondary thread yield great result
combining the best of each approach. This might be implemented in later
changesets.

In all cases, using mmap has a great effect on memory usage when many processes
run in parallel on the same machine.

### Benchmarks

# What did I run

A couple of month back I ran a large benchmark campaign to assess the impact of
various approach for using mmap with the revlog (and other files), it
highlighted a few benchmarks that capture the impact of the changes well. So to
validate this change I checked the following:

- log command displaying various revisions
  (read the changelog index)
- log command displaying the patch of listed revisions
  (read the changelog index, the manifest index and a few files indexes)
- unbundling a few revisions
  (read and write changelog, manifest and few files indexes, and walk the graph
  to update some cache)
- pushing a few revisions
  (read and write changelog, manifest and few files indexes, walk the graph to
  update some cache, performs various accesses locally and remotely during
  discovery)

Benchmarks were run using the default module policy (c+py) and the rust one. No
significant difference were found between the two implementation, so we will
present result using the default policy (unless otherwise specified).

I ran them on a few repositories :

- mercurial: a "public changeset only" copy of mercurial from 2018-08-01 using
  zstd compression and sparse-revlog

- pypy: a copy of pypy from 2018-08-01 using zstd compression and sparse-revlog

- netbeans: a copy of netbeans from 2018-08-01 using zstd compression and
  sparse-revlog

- mozilla-try: a copy of mozilla-try from 2019-02-18 using zstd compression and
  sparse-revlog

- mozilla-try persistent-nodemap: Same as the above but with a persistent
  nodemap. Used for the log --patch benchmark only

# Results

For the smaller repositories (mercurial, pypy), the impact of mmap is almost
imperceptible, other cost dominating the operation. The impact of prepopulating
is undiscernible in the benchmark we ran.

For larger repositories the benchmark support explanation given above:

On netbeans, the log can be about 1% faster without repopulation (for a
difference < 100ms) but unbundle becomes a bit slower, even when small.

### data-env-vars.name                             = netbeans-2018-08-01-zstd-sparse-revlog
  # benchmark.name                                 = hg.command.unbundle
  # benchmark.variants.issue6528                   = disabled
  # benchmark.variants.reuse-external-delta-parent = yes
  # benchmark.variants.revs                        = any-1-extra-rev
  # benchmark.variants.source                      = unbundle
  # benchmark.variants.verbosity                   = quiet
with-populate: 0.240157
no-populate:   0.265087  (+10.38%, +0.02)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 1.459518
no-populate:   1.481290   (+1.49%, +0.02)
 ## benchmark.name                                 = hg.command.push
  # benchmark.variants.explicit-rev                = none
  # benchmark.variants.issue6528                   = disabled
  # benchmark.variants.protocol                    = ssh
  # benchmark.variants.reuse-external-delta-parent = yes
  # benchmark.variants.revs                        = any-1-extra-rev
with-populate: 0.771919
no-populate:   0.792025   (+2.60%, +0.02)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 1.459518
no-populate:   1.481290   (+1.49%, +0.02)


For mozilla-try, the "slow down" from pre-populate for small `hg log` is more
visible, but still small in absolute time. (using rust value for the persistent
nodemap value to be relevant).

### data-env-vars.name            = mozilla-try-2019-02-18-ds2-pnm
  # benchmark.name                = hg.command.log
  # bin-env-vars.hg.flavor        = rust
  # benchmark.variants.patch      = yes
  # benchmark.variants.limit-rev  = 1
with-populate: 0.237813
no-populate:   0.229452   (-3.52%, -0.01)
  # benchmark.variants.limit-rev  = 10
  # benchmark.variants.patch      = yes
with-populate: 1.213578
no-populate:   1.205189
### data-env-vars.name            = mozilla-try-2019-02-18-zstd-sparse-revlog
  # benchmark.variants.limit-rev  = 1000
  # benchmark.variants.patch      = no
  # benchmark.variants.rev        = tip
with-populate: 0.198607
no-populate:   0.195038   (-1.80%, -0.00)

However pre-populating provide a significant boost on more complex operations
like unbundle or push:

### data-env-vars.name                             = mozilla-try-2019-02-18-zstd-sparse-revlog
  # benchmark.name                                 = hg.command.push
  # benchmark.variants.explicit-rev                = none
  # benchmark.variants.issue6528                   = disabled
  # benchmark.variants.protocol                    = ssh
  # benchmark.variants.reuse-external-delta-parent = yes
  # benchmark.variants.revs                        = any-1-extra-rev
with-populate: 4.798632
no-populate:   4.953295   (+3.22%, +0.15)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 4.903618
no-populate:   5.014963   (+2.27%, +0.11)
 ## benchmark.name                                 = hg.command.unbundle
  # benchmark.variants.revs                        = any-1-extra-rev
with-populate: 1.423411
no-populate:   1.585365  (+11.38%, +0.16)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 1.537909
no-populate:   1.688489   (+9.79%, +0.15)

Set up a base, local, and remote changeset, as well as the working copy state.
Files names are of the form base_remote_local_working-copy. For example,
content1_content2_content1_content2-untracked represents a
file that was modified in the remote changeset, left untouched in the
local changeset, and then modified in the working copy to match the
remote content, then finally forgotten.

  $ hg init repo
  $ cd repo

Create base changeset

  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 3 1
  $ hg addremove -q --similarity 0
  $ hg commit -qm 'base'

Create remote changeset

  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 3 2
  $ hg addremove -q --similarity 0
  $ hg commit -qm 'remote'

Create local changeset

  $ hg update -q 0
  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 3 3
  $ hg addremove -q --similarity 0
  $ hg commit -qm 'local'

Set up working directory

  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 3 wc
  $ hg addremove -q --similarity 0
  $ hg forget *_*_*_*-untracked
  $ rm *_*_*_missing-*

  $ hg status -A
  M content1_content1_content1_content4-tracked
  M content1_content1_content3_content1-tracked
  M content1_content1_content3_content4-tracked
  M content1_content2_content1_content2-tracked
  M content1_content2_content1_content4-tracked
  M content1_content2_content2_content1-tracked
  M content1_content2_content2_content4-tracked
  M content1_content2_content3_content1-tracked
  M content1_content2_content3_content2-tracked
  M content1_content2_content3_content4-tracked
  M content1_missing_content1_content4-tracked
  M content1_missing_content3_content1-tracked
  M content1_missing_content3_content4-tracked
  M missing_content2_content2_content4-tracked
  M missing_content2_content3_content2-tracked
  M missing_content2_content3_content4-tracked
  M missing_missing_content3_content4-tracked
  A content1_content1_missing_content1-tracked
  A content1_content1_missing_content4-tracked
  A content1_content2_missing_content1-tracked
  A content1_content2_missing_content2-tracked
  A content1_content2_missing_content4-tracked
  A content1_missing_missing_content1-tracked
  A content1_missing_missing_content4-tracked
  A missing_content2_missing_content2-tracked
  A missing_content2_missing_content4-tracked
  A missing_missing_missing_content4-tracked
  R content1_content1_content1_content1-untracked
  R content1_content1_content1_content4-untracked
  R content1_content1_content1_missing-untracked
  R content1_content1_content3_content1-untracked
  R content1_content1_content3_content3-untracked
  R content1_content1_content3_content4-untracked
  R content1_content1_content3_missing-untracked
  R content1_content2_content1_content1-untracked
  R content1_content2_content1_content2-untracked
  R content1_content2_content1_content4-untracked
  R content1_content2_content1_missing-untracked
  R content1_content2_content2_content1-untracked
  R content1_content2_content2_content2-untracked
  R content1_content2_content2_content4-untracked
  R content1_content2_content2_missing-untracked
  R content1_content2_content3_content1-untracked
  R content1_content2_content3_content2-untracked
  R content1_content2_content3_content3-untracked
  R content1_content2_content3_content4-untracked
  R content1_content2_content3_missing-untracked
  R content1_missing_content1_content1-untracked
  R content1_missing_content1_content4-untracked
  R content1_missing_content1_missing-untracked
  R content1_missing_content3_content1-untracked
  R content1_missing_content3_content3-untracked
  R content1_missing_content3_content4-untracked
  R content1_missing_content3_missing-untracked
  R missing_content2_content2_content2-untracked
  R missing_content2_content2_content4-untracked
  R missing_content2_content2_missing-untracked
  R missing_content2_content3_content2-untracked
  R missing_content2_content3_content3-untracked
  R missing_content2_content3_content4-untracked
  R missing_content2_content3_missing-untracked
  R missing_missing_content3_content3-untracked
  R missing_missing_content3_content4-untracked
  R missing_missing_content3_missing-untracked
  ! content1_content1_content1_missing-tracked
  ! content1_content1_content3_missing-tracked
  ! content1_content1_missing_missing-tracked
  ! content1_content2_content1_missing-tracked
  ! content1_content2_content2_missing-tracked
  ! content1_content2_content3_missing-tracked
  ! content1_content2_missing_missing-tracked
  ! content1_missing_content1_missing-tracked
  ! content1_missing_content3_missing-tracked
  ! content1_missing_missing_missing-tracked
  ! missing_content2_content2_missing-tracked
  ! missing_content2_content3_missing-tracked
  ! missing_content2_missing_missing-tracked
  ! missing_missing_content3_missing-tracked
  ! missing_missing_missing_missing-tracked
  ? content1_content1_missing_content1-untracked
  ? content1_content1_missing_content4-untracked
  ? content1_content2_missing_content1-untracked
  ? content1_content2_missing_content2-untracked
  ? content1_content2_missing_content4-untracked
  ? content1_missing_missing_content1-untracked
  ? content1_missing_missing_content4-untracked
  ? missing_content2_missing_content2-untracked
  ? missing_content2_missing_content4-untracked
  ? missing_missing_missing_content4-untracked
  C content1_content1_content1_content1-tracked
  C content1_content1_content3_content3-tracked
  C content1_content2_content1_content1-tracked
  C content1_content2_content2_content2-tracked
  C content1_content2_content3_content3-tracked
  C content1_missing_content1_content1-tracked
  C content1_missing_content3_content3-tracked
  C missing_content2_content2_content2-tracked
  C missing_content2_content3_content3-tracked
  C missing_missing_content3_content3-tracked

Merge with remote

# Notes:
# - local and remote changed content1_content2_*_content2-untracked
#   in the same way, so it could potentially be left alone

  $ hg merge -f --tool internal:merge3 'desc("remote")' 2>&1 | tee $TESTTMP/merge-output-1
  file 'content1_missing_content1_content4-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_missing_content3_content3-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_missing_content3_content4-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_missing_missing_content4-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_content3-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_content1_content4-tracked
  warning: conflicts while merging content1_content2_content1_content4-tracked! (edit, then use 'hg resolve --mark')
  merging content1_content2_content2_content1-tracked
  merging content1_content2_content2_content4-tracked
  warning: conflicts while merging content1_content2_content2_content4-tracked! (edit, then use 'hg resolve --mark')
  merging content1_content2_content3_content1-tracked
  merging content1_content2_content3_content3-tracked
  warning: conflicts while merging content1_content2_content3_content3-tracked! (edit, then use 'hg resolve --mark')
  merging content1_content2_content3_content4-tracked
  warning: conflicts while merging content1_content2_content3_content4-tracked! (edit, then use 'hg resolve --mark')
  merging content1_content2_missing_content1-tracked
  merging content1_content2_missing_content4-tracked
  warning: conflicts while merging content1_content2_missing_content4-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_content2_content4-tracked
  warning: conflicts while merging missing_content2_content2_content4-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_content3_content3-tracked
  warning: conflicts while merging missing_content2_content3_content3-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_content3_content4-tracked
  warning: conflicts while merging missing_content2_content3_content4-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_missing_content4-tracked
  warning: conflicts while merging missing_content2_missing_content4-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_missing_content4-untracked
  warning: conflicts while merging missing_content2_missing_content4-untracked! (edit, then use 'hg resolve --mark')
  18 files updated, 3 files merged, 8 files removed, 35 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon

Check which files need to be resolved (should correspond to the output above).
This should be the files for which the base (1st filename segment), the remote
(2nd segment) and the working copy (4th segment) are all different.

Interestingly, one untracked file got merged and added, which corresponds to the
odd 'if force and branchmerge and different' case in manifestmerge().

  $ hg resolve -l
  U content1_content2_content1_content1-untracked
  U content1_content2_content1_content2-untracked
  U content1_content2_content1_content4-tracked
  U content1_content2_content1_content4-untracked
  U content1_content2_content1_missing-tracked
  U content1_content2_content1_missing-untracked
  R content1_content2_content2_content1-tracked
  U content1_content2_content2_content1-untracked
  U content1_content2_content2_content2-untracked
  U content1_content2_content2_content4-tracked
  U content1_content2_content2_content4-untracked
  U content1_content2_content2_missing-tracked
  U content1_content2_content2_missing-untracked
  R content1_content2_content3_content1-tracked
  U content1_content2_content3_content1-untracked
  U content1_content2_content3_content2-untracked
  U content1_content2_content3_content3-tracked
  U content1_content2_content3_content3-untracked
  U content1_content2_content3_content4-tracked
  U content1_content2_content3_content4-untracked
  U content1_content2_content3_missing-tracked
  U content1_content2_content3_missing-untracked
  R content1_content2_missing_content1-tracked
  U content1_content2_missing_content1-untracked
  U content1_content2_missing_content2-untracked
  U content1_content2_missing_content4-tracked
  U content1_content2_missing_content4-untracked
  U content1_content2_missing_missing-tracked
  U content1_content2_missing_missing-untracked
  U content1_missing_content1_content4-tracked
  U content1_missing_content3_content3-tracked
  U content1_missing_content3_content4-tracked
  U content1_missing_missing_content4-tracked
  U missing_content2_content2_content4-tracked
  U missing_content2_content3_content3-tracked
  U missing_content2_content3_content4-tracked
  U missing_content2_missing_content4-tracked
  U missing_content2_missing_content4-untracked

Check status and file content

Some files get added (e.g. content1_content2_content1_content1-untracked)

It is not intuitive that content1_content2_content1_content4-tracked gets
merged while content1_content2_content1_content4-untracked gets overwritten.
Any *_content2_*-untracked triggers the modified/deleted prompt and then gets
overwritten.

A lot of untracked files become tracked, for example
content1_content2_content2_content2-untracked.

*_missing_missing_missing-tracked is reported as removed ('R'), which
doesn't make sense since the file did not exist in the parent, but on the
other hand, merged-in additions are reported as modifications, which is
almost as strange.

missing_missing_content3_missing-tracked becomes removed ('R'), even though
the remote side did not touch the file

  $ checkstatus() {
  >   for f in `"$PYTHON" $TESTDIR/generate-working-copy-states.py filelist 3`
  >   do
  >     echo
  >     hg status -A $f
  >     if test -f $f
  >     then
  >       cat $f
  >     else
  >       echo '<missing>'
  >     fi
  >   done
  > }
  $ checkstatus 2>&1 | tee $TESTTMP/status1
  
  C content1_content1_content1_content1-tracked
  content1
  
  R content1_content1_content1_content1-untracked
  content1
  
  M content1_content1_content1_content4-tracked
  content4
  
  R content1_content1_content1_content4-untracked
  content4
  
  ! content1_content1_content1_missing-tracked
  <missing>
  
  R content1_content1_content1_missing-untracked
  <missing>
  
  M content1_content1_content3_content1-tracked
  content1
  
  R content1_content1_content3_content1-untracked
  content1
  
  C content1_content1_content3_content3-tracked
  content3
  
  R content1_content1_content3_content3-untracked
  content3
  
  M content1_content1_content3_content4-tracked
  content4
  
  R content1_content1_content3_content4-untracked
  content4
  
  ! content1_content1_content3_missing-tracked
  <missing>
  
  R content1_content1_content3_missing-untracked
  <missing>
  
  A content1_content1_missing_content1-tracked
  content1
  
  ? content1_content1_missing_content1-untracked
  content1
  
  A content1_content1_missing_content4-tracked
  content4
  
  ? content1_content1_missing_content4-untracked
  content4
  
  ! content1_content1_missing_missing-tracked
  <missing>
  
  content1_content1_missing_missing-untracked: * (glob)
  <missing>
  
  M content1_content2_content1_content1-tracked
  content2
  
  M content1_content2_content1_content1-untracked
  content2
  
  M content1_content2_content1_content2-tracked
  content2
  
  M content1_content2_content1_content2-untracked
  content2
  
  M content1_content2_content1_content4-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 8ef80617fa20 - test: base
  content1
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M content1_content2_content1_content4-untracked
  content2
  
  M content1_content2_content1_missing-tracked
  content2
  
  M content1_content2_content1_missing-untracked
  content2
  
  M content1_content2_content2_content1-tracked
  content2
  
  M content1_content2_content2_content1-untracked
  content2
  
  C content1_content2_content2_content2-tracked
  content2
  
  M content1_content2_content2_content2-untracked
  content2
  
  M content1_content2_content2_content4-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 8ef80617fa20 - test: base
  content1
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M content1_content2_content2_content4-untracked
  content2
  
  M content1_content2_content2_missing-tracked
  content2
  
  M content1_content2_content2_missing-untracked
  content2
  
  M content1_content2_content3_content1-tracked
  content2
  
  M content1_content2_content3_content1-untracked
  content2
  
  M content1_content2_content3_content2-tracked
  content2
  
  M content1_content2_content3_content2-untracked
  content2
  
  M content1_content2_content3_content3-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content3
  ||||||| common ancestor: 8ef80617fa20 - test: base
  content1
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M content1_content2_content3_content3-untracked
  content2
  
  M content1_content2_content3_content4-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 8ef80617fa20 - test: base
  content1
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M content1_content2_content3_content4-untracked
  content2
  
  M content1_content2_content3_missing-tracked
  content2
  
  M content1_content2_content3_missing-untracked
  content2
  
  M content1_content2_missing_content1-tracked
  content2
  
  M content1_content2_missing_content1-untracked
  content2
  
  M content1_content2_missing_content2-tracked
  content2
  
  M content1_content2_missing_content2-untracked
  content2
  
  M content1_content2_missing_content4-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 8ef80617fa20 - test: base
  content1
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M content1_content2_missing_content4-untracked
  content2
  
  M content1_content2_missing_missing-tracked
  content2
  
  M content1_content2_missing_missing-untracked
  content2
  
  R content1_missing_content1_content1-tracked
  <missing>
  
  R content1_missing_content1_content1-untracked
  content1
  
  M content1_missing_content1_content4-tracked
  content4
  
  R content1_missing_content1_content4-untracked
  content4
  
  R content1_missing_content1_missing-tracked
  <missing>
  
  R content1_missing_content1_missing-untracked
  <missing>
  
  R content1_missing_content3_content1-tracked
  <missing>
  
  R content1_missing_content3_content1-untracked
  content1
  
  C content1_missing_content3_content3-tracked
  content3
  
  R content1_missing_content3_content3-untracked
  content3
  
  M content1_missing_content3_content4-tracked
  content4
  
  R content1_missing_content3_content4-untracked
  content4
  
  R content1_missing_content3_missing-tracked
  <missing>
  
  R content1_missing_content3_missing-untracked
  <missing>
  
  R content1_missing_missing_content1-tracked
  <missing>
  
  ? content1_missing_missing_content1-untracked
  content1
  
  A content1_missing_missing_content4-tracked
  content4
  
  ? content1_missing_missing_content4-untracked
  content4
  
  R content1_missing_missing_missing-tracked
  <missing>
  
  content1_missing_missing_missing-untracked: * (glob)
  <missing>
  
  C missing_content2_content2_content2-tracked
  content2
  
  M missing_content2_content2_content2-untracked
  content2
  
  M missing_content2_content2_content4-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 000000000000 - : 
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M missing_content2_content2_content4-untracked
  content2
  
  M missing_content2_content2_missing-tracked
  content2
  
  M missing_content2_content2_missing-untracked
  content2
  
  M missing_content2_content3_content2-tracked
  content2
  
  M missing_content2_content3_content2-untracked
  content2
  
  M missing_content2_content3_content3-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content3
  ||||||| common ancestor: 000000000000 - : 
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M missing_content2_content3_content3-untracked
  content2
  
  M missing_content2_content3_content4-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 000000000000 - : 
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M missing_content2_content3_content4-untracked
  content2
  
  M missing_content2_content3_missing-tracked
  content2
  
  M missing_content2_content3_missing-untracked
  content2
  
  M missing_content2_missing_content2-tracked
  content2
  
  M missing_content2_missing_content2-untracked
  content2
  
  M missing_content2_missing_content4-tracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 000000000000 - : 
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M missing_content2_missing_content4-untracked
  <<<<<<< working copy:    0447570f1af6 - test: local
  content4
  ||||||| common ancestor: 000000000000 - : 
  =======
  content2
  >>>>>>> merge rev:       85100b8c675b - test: remote
  
  M missing_content2_missing_missing-tracked
  content2
  
  M missing_content2_missing_missing-untracked
  content2
  
  C missing_missing_content3_content3-tracked
  content3
  
  R missing_missing_content3_content3-untracked
  content3
  
  M missing_missing_content3_content4-tracked
  content4
  
  R missing_missing_content3_content4-untracked
  content4
  
  R missing_missing_content3_missing-tracked
  <missing>
  
  R missing_missing_content3_missing-untracked
  <missing>
  
  A missing_missing_missing_content4-tracked
  content4
  
  ? missing_missing_missing_content4-untracked
  content4
  
  R missing_missing_missing_missing-tracked
  <missing>
  
  missing_missing_missing_missing-untracked: * (glob)
  <missing>

  $ for f in `"$PYTHON" $TESTDIR/generate-working-copy-states.py filelist 3`
  > do
  >   if test -f ${f}.orig
  >   then
  >     echo ${f}.orig:
  >     cat ${f}.orig
  >   fi
  > done
  content1_content2_content1_content4-tracked.orig:
  content4
  content1_content2_content2_content4-tracked.orig:
  content4
  content1_content2_content3_content3-tracked.orig:
  content3
  content1_content2_content3_content4-tracked.orig:
  content4
  content1_content2_missing_content4-tracked.orig:
  content4
  missing_content2_content2_content4-tracked.orig:
  content4
  missing_content2_content3_content3-tracked.orig:
  content3
  missing_content2_content3_content4-tracked.orig:
  content4
  missing_content2_missing_content4-tracked.orig:
  content4
  missing_content2_missing_content4-untracked.orig:
  content4

Re-resolve and check status

  $ hg resolve --unmark --all
  $ hg resolve --all --tool :local
  (no more unresolved files)
  $ hg resolve --unmark --all
  $ hg resolve --all --tool internal:merge3
  file 'content1_content2_content1_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_content1_content4-tracked
  warning: conflicts while merging content1_content2_content1_content4-tracked! (edit, then use 'hg resolve --mark')
  file 'content1_content2_content1_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content1_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_content2_content1-tracked
  file 'content1_content2_content2_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_content2_content4-tracked
  warning: conflicts while merging content1_content2_content2_content4-tracked! (edit, then use 'hg resolve --mark')
  file 'content1_content2_content2_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content2_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_content3_content1-tracked
  file 'content1_content2_content3_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_content3_content3-tracked
  warning: conflicts while merging content1_content2_content3_content3-tracked! (edit, then use 'hg resolve --mark')
  file 'content1_content2_content3_content3-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_content3_content4-tracked
  warning: conflicts while merging content1_content2_content3_content4-tracked! (edit, then use 'hg resolve --mark')
  file 'content1_content2_content3_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_content3_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_missing_content1-tracked
  file 'content1_content2_missing_content1-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_content2-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  merging content1_content2_missing_content4-tracked
  warning: conflicts while merging content1_content2_missing_content4-tracked! (edit, then use 'hg resolve --mark')
  file 'content1_content2_missing_content4-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_missing-tracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_content2_missing_missing-untracked' was deleted in local [working copy] but was modified in other [merge rev].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_missing_content1_content4-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_missing_content3_content3-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_missing_content3_content4-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  file 'content1_missing_missing_content4-tracked' was deleted in other [merge rev] but was modified in local [working copy].
  You can use (c)hanged version, (d)elete, or leave (u)nresolved.
  What do you want to do? u
  merging missing_content2_content2_content4-tracked
  warning: conflicts while merging missing_content2_content2_content4-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_content3_content3-tracked
  warning: conflicts while merging missing_content2_content3_content3-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_content3_content4-tracked
  warning: conflicts while merging missing_content2_content3_content4-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_missing_content4-tracked
  warning: conflicts while merging missing_content2_missing_content4-tracked! (edit, then use 'hg resolve --mark')
  merging missing_content2_missing_content4-untracked
  warning: conflicts while merging missing_content2_missing_content4-untracked! (edit, then use 'hg resolve --mark')
  [1]
  $ checkstatus > $TESTTMP/status2 2>&1
  $ cmp $TESTTMP/status1 $TESTTMP/status2 || diff -U8 $TESTTMP/status1 $TESTTMP/status2

Set up working directory again

  $ hg -q update --clean 2
  $ hg --config extensions.purge= purge
  $ "$PYTHON" $TESTDIR/generate-working-copy-states.py state 3 wc
  $ hg addremove -q --similarity 0
  $ hg forget *_*_*_*-untracked
  $ rm *_*_*_missing-*

Merge with checkunknown = warn, see that behavior is the same as before
  $ hg merge -f --tool internal:merge3 'desc("remote")' --config merge.checkunknown=warn > $TESTTMP/merge-output-2 2>&1
  [1]
  $ cmp $TESTTMP/merge-output-1 $TESTTMP/merge-output-2 || diff -U8 $TESTTMP/merge-output-1 $TESTTMP/merge-output-2