view tests/test-diffstat.t @ 44363:f7459da77f23

nodemap: introduce an option to use mmap to read the nodemap mapping

The performance and memory benefit is much greater if we don't have to copy all
the data in memory for each information. So we introduce an option (on by
default) to read the data using mmap.

This changeset is the last one definition the API for index support nodemap
data. (they have to be able to use the mmaping).

Below are some benchmark comparing the best we currently have in 5.3 with the
final step of this series (using the persistent nodemap implementation in
Rust). The benchmark run `hg perfindex` with various revset and the following
variants:

Before:

 * do not use the persistent nodemap
 * use the CPython implementation of the index for nodemap
 * use mmapping of the changelog index

After:

 * use the MixedIndex Rust code, with the NodeTree object for nodemap access
   (still in review)
 * use the persistent nodemap data from disk
 * access the persistent nodemap data through mmap
 * use mmapping of the changelog index

The persistent nodemap greatly speed up  most operation on very large
repositories. Some of the previously very fast lookup end up a bit slower because
the persistent nodemap has to be setup. However the absolute slowdown is very
small and won't matters in the big picture.

Here are some numbers (in seconds) for the reference copy of mozilla-try:

Revset            Before   After     abs-change speedup

-10000:           0.004622 0.005532   0.000910  ×   0.83
-10:              0.000050 0.000132   0.000082  ×   0.37
tip               0.000052 0.000085   0.000033  ×   0.61
0 + (-10000:)     0.028222 0.005337  -0.022885  ×   5.29
0                 0.023521 0.000084  -0.023437  × 280.01
(-10000:) + 0     0.235539 0.005308  -0.230231  ×  44.37
(-10:) + :9       0.232883 0.000180  -0.232703  ×1293.79
(-10000:) + (:99) 0.238735 0.005358  -0.233377  ×  44.55
:99 + (-10000:)   0.317942 0.005593  -0.312349  ×  56.84
:9 + (-10:)       0.313372 0.000179  -0.313193  ×1750.68
:9                0.316450 0.000143  -0.316307  ×2212.93


On smaller repositories, the cost of nodemap related operation is not as big, so
the win is much more modest. Yet it helps shaving a handful of millisecond here
and there.

Here are some numbers (in seconds) for the reference copy of mercurial:

Revset            Before   After     abs-change speedup
-10:              0.000065 0.000097   0.000032  × 0.67
tip               0.000063 0.000078   0.000015  × 0.80
0                 0.000561 0.000079  -0.000482  × 7.10
-10000:           0.004609 0.003648  -0.000961  × 1.26
0 + (-10000:)     0.005023 0.003715  -0.001307  × 1.35
(-10:) + :9       0.002187 0.000108  -0.002079  ×20.25
(-10000:) + 0     0.006252 0.003716  -0.002536  × 1.68
(-10000:) + (:99) 0.006367 0.003707  -0.002660  × 1.71
:9 + (-10:)       0.003846 0.000110  -0.003736  ×34.96
:9                0.003854 0.000099  -0.003755  ×38.92
:99 + (-10000:)   0.007644 0.003778  -0.003866  × 2.02

Differential Revision: https://phab.mercurial-scm.org/D7894

  $ hg init repo
  $ cd repo
  $ i=0; while [ "$i" -lt 213 ]; do echo a >> a; i=`expr $i + 1`; done
  $ hg add a
  $ cp a b
  $ hg add b

Wide diffstat:

  $ hg diff --stat
   a |  213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
   b |  213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
   2 files changed, 426 insertions(+), 0 deletions(-)

diffstat width:

  $ COLUMNS=24 hg diff --config ui.interactive=true --stat
   a |  213 ++++++++++++++
   b |  213 ++++++++++++++
   2 files changed, 426 insertions(+), 0 deletions(-)

  $ hg ci -m adda

  $ cat >> a <<EOF
  > a
  > a
  > a
  > EOF

Narrow diffstat:

  $ hg diff --stat
   a |  3 +++
   1 files changed, 3 insertions(+), 0 deletions(-)

  $ hg ci -m appenda

  >>> open("c", "wb").write(b"\0") and None
  $ touch d
  $ hg add c d

Binary diffstat:

  $ hg diff --stat
   c |  Bin 
   1 files changed, 0 insertions(+), 0 deletions(-)

Binary git diffstat:

  $ hg diff --stat --git
   c |  Bin 
   d |    0 
   2 files changed, 0 insertions(+), 0 deletions(-)

  $ hg ci -m createb

  >>> open("file with spaces", "wb").write(b"\0") and None
  $ hg add "file with spaces"

Filename with spaces diffstat:

  $ hg diff --stat
   file with spaces |  Bin 
   1 files changed, 0 insertions(+), 0 deletions(-)

Filename with spaces git diffstat:

  $ hg diff --stat --git
   file with spaces |  Bin 
   1 files changed, 0 insertions(+), 0 deletions(-)

Filename without "a/" or "b/" (issue5759):

  $ hg diff --config 'diff.noprefix=1' -c1 --stat --git
   a |  3 +++
   1 files changed, 3 insertions(+), 0 deletions(-)
  $ hg diff --config 'diff.noprefix=1' -c2 --stat --git
   c |  Bin 
   d |    0 
   2 files changed, 0 insertions(+), 0 deletions(-)

  $ hg log --config 'diff.noprefix=1' -r '1:' -p --stat --git
  changeset:   1:3a95b07bb77f
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     appenda
  
   a |  3 +++
   1 files changed, 3 insertions(+), 0 deletions(-)
  
  diff --git a a
  --- a
  +++ a
  @@ -211,3 +211,6 @@
   a
   a
   a
  +a
  +a
  +a
  
  changeset:   2:c60a6c753773
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     createb
  
   c |  Bin 
   d |    0 
   2 files changed, 0 insertions(+), 0 deletions(-)
  
  diff --git c c
  new file mode 100644
  index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..f76dd238ade08917e6712764a16a22005a50573d
  GIT binary patch
  literal 1
  Ic${MZ000310RR91
  
  diff --git d d
  new file mode 100644
  

diffstat within directories:

  $ hg rm -f 'file with spaces'

  $ mkdir dir1 dir2
  $ echo new1 > dir1/new
  $ echo new2 > dir2/new
  $ hg add dir1/new dir2/new
  $ hg diff --stat
   dir1/new |  1 +
   dir2/new |  1 +
   2 files changed, 2 insertions(+), 0 deletions(-)

  $ hg diff --stat --root dir1
   new |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)

  $ hg diff --stat --root dir1 dir2
  warning: dir2 not inside relative root dir1

  $ hg diff --stat --root dir1 -I dir1/old

  $ cd dir1
  $ hg diff --stat .
   dir1/new |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)
  $ hg diff --stat . --config ui.relative-paths=yes
   new |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)
  $ hg diff --stat --root .
   new |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)

  $ hg diff --stat --root . --config ui.relative-paths=yes
   new |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)
--root trumps ui.relative-paths
  $ hg diff --stat --root .. --config ui.relative-paths=yes
   new         |  1 +
   ../dir2/new |  1 +
   2 files changed, 2 insertions(+), 0 deletions(-)
  $ hg diff --stat --root ../dir1 ../dir2
  warning: ../dir2 not inside relative root .

  $ hg diff --stat --root . -I old

  $ cd ..

Files with lines beginning with '--' or '++' should be properly counted in diffstat

  $ hg up -Cr tip
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ rm dir1/new
  $ rm dir2/new
  $ rm "file with spaces"
  $ cat > file << EOF
  > line 1
  > line 2
  > line 3
  > EOF
  $ hg commit -Am file
  adding file

Lines added starting with '--' should count as additions
  $ cat > file << EOF
  > line 1
  > -- line 2, with dashes
  > line 3
  > EOF

  $ hg diff --root .
  diff -r be1569354b24 file
  --- a/file	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file	* (glob)
  @@ -1,3 +1,3 @@
   line 1
  -line 2
  +-- line 2, with dashes
   line 3

  $ hg diff --root . --stat
   file |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)

Lines changed starting with '--' should count as deletions
  $ hg commit -m filev2
  $ cat > file << EOF
  > line 1
  > -- line 2, with dashes, changed again
  > line 3
  > EOF

  $ hg diff --root .
  diff -r 160f7c034df6 file
  --- a/file	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file	* (glob)
  @@ -1,3 +1,3 @@
   line 1
  --- line 2, with dashes
  +-- line 2, with dashes, changed again
   line 3

  $ hg diff --root . --stat
   file |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)

Lines changed starting with '--' should count as deletions
and starting with '++' should count as additions
  $ cat > file << EOF
  > line 1
  > ++ line 2, switched dashes to plusses
  > line 3
  > EOF

  $ hg diff --root .
  diff -r 160f7c034df6 file
  --- a/file	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file	* (glob)
  @@ -1,3 +1,3 @@
   line 1
  --- line 2, with dashes
  +++ line 2, switched dashes to plusses
   line 3

  $ hg diff --root . --stat
   file |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)

When a file is renamed, --git shouldn't loss the info about old file
  $ hg init issue6025
  $ cd issue6025
  $ echo > a
  $ hg ci -Am 'add a'
  adding a
  $ hg mv a b
  $ hg diff --git
  diff --git a/a b/b
  rename from a
  rename to b
  $ hg diff --stat
   a |  1 -
   b |  1 +
   2 files changed, 1 insertions(+), 1 deletions(-)
  $ hg diff --stat --git
   a => b |  0 
   1 files changed, 0 insertions(+), 0 deletions(-)
-- filename may contain whitespaces
  $ echo > c
  $ hg ci -Am 'add c'
  adding c
  $ hg mv c 'new c'
  $ hg diff --git
  diff --git a/c b/new c
  rename from c
  rename to new c
  $ hg diff --stat
   c     |  1 -
   new c |  1 +
   2 files changed, 1 insertions(+), 1 deletions(-)
  $ hg diff --stat --git
   c => new c |  0 
   1 files changed, 0 insertions(+), 0 deletions(-)

Make sure `diff --stat -q --config diff.git-0` shows stat (issue4037)

  $ hg status
  A new c
  R c
  $ hg diff --stat -q
   c     |  1 -
   new c |  1 +
   2 files changed, 1 insertions(+), 1 deletions(-)