view tests/test-diff-binary-file.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 a
  $ cd a
  $ cp "$TESTDIR/binfile.bin" .
  $ hg add binfile.bin
  $ hg ci -m 'add binfile.bin'

  $ echo >> binfile.bin
  $ hg ci -m 'change binfile.bin'

  $ hg revert -r 0 binfile.bin
  $ hg ci -m 'revert binfile.bin'
  $ hg cp binfile.bin nonbinfile
  $ echo text > nonbinfile
  $ hg ci -m 'make non-binary copy of binary file'

  $ hg diff --nodates -r 0 -r 1
  diff -r 48b371597640 -r acea2ab458c8 binfile.bin
  Binary file binfile.bin has changed

  $ hg diff --nodates -r 0 -r 2

  $ hg diff --git -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  index 37ba3d1c6f17137d9c5f5776fa040caf5fe73ff9..58dc31a9e2f40f74ff3b45903f7d620b8e5b7356
  GIT binary patch
  literal 594
  zc$@)J0<HatP)<h;3K|Lk000e1NJLTq000mG000mO0ssI2kdbIM00009a7bBm000XU
  z000XU0RWnu7ytkO2XskIMF-Uh9TW;VpMjwv0005-Nkl<ZD9@FWPs=e;7{<>W$NUkd
  zX$nnYLt$-$V!?uy+1V%`z&Eh=ah|duER<4|QWhju3gb^nF*8iYobxWG-qqXl=2~5M
  z*IoDB)sG^CfNuoBmqLTVU^<;@nwHP!1wrWd`{(mHo6VNXWtyh{alzqmsH*yYzpvLT
  zLdY<T=ks|woh-`&01!ej#(xbV1f|pI*=%;d-%F*E*X#ZH`4I%6SS+$EJDE&ct=8po
  ziN#{?_j|kD%Cd|oiqds`xm@;oJ-^?NG3Gdqrs?5u*zI;{nogxsx~^|Fn^Y?Gdc6<;
  zfMJ+iF1J`LMx&A2?dEwNW8ClebzPTbIh{@$hS6*`kH@1d%Lo7fA#}N1)oN7`gm$~V
  z+wDx#)OFqMcE{s!JN0-xhG8ItAjVkJwEcb`3WWlJfU2r?;Pd%dmR+q@mSri5q9_W-
  zaR2~ECX?B2w+zELozC0s*6Z~|QG^f{3I#<`?)Q7U-JZ|q5W;9Q8i_=pBuSzunx=U;
  z9C)5jBoYw9^?EHyQl(M}1OlQcCX>lXB*ODN003Z&P17_@)3Pi=i0wb04<W?v-u}7K
  zXmmQA+wDgE!qR9o8jr`%=ab_&uh(l?R=r;Tjiqon91I2-hIu?57~@*4h7h9uORK#=
  gQItJW-{SoTm)8|5##k|m00000NkvXXu0mjf3JwksH2?qr
  

  $ hg diff --git -r 0 -r 2

  $ hg diff --config diff.nobinary=True --git -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  Binary file binfile.bin has changed

  $ HGPLAIN=1 hg diff --config diff.nobinary=True --git -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  index 37ba3d1c6f17137d9c5f5776fa040caf5fe73ff9..58dc31a9e2f40f74ff3b45903f7d620b8e5b7356
  GIT binary patch
  literal 594
  zc$@)J0<HatP)<h;3K|Lk000e1NJLTq000mG000mO0ssI2kdbIM00009a7bBm000XU
  z000XU0RWnu7ytkO2XskIMF-Uh9TW;VpMjwv0005-Nkl<ZD9@FWPs=e;7{<>W$NUkd
  zX$nnYLt$-$V!?uy+1V%`z&Eh=ah|duER<4|QWhju3gb^nF*8iYobxWG-qqXl=2~5M
  z*IoDB)sG^CfNuoBmqLTVU^<;@nwHP!1wrWd`{(mHo6VNXWtyh{alzqmsH*yYzpvLT
  zLdY<T=ks|woh-`&01!ej#(xbV1f|pI*=%;d-%F*E*X#ZH`4I%6SS+$EJDE&ct=8po
  ziN#{?_j|kD%Cd|oiqds`xm@;oJ-^?NG3Gdqrs?5u*zI;{nogxsx~^|Fn^Y?Gdc6<;
  zfMJ+iF1J`LMx&A2?dEwNW8ClebzPTbIh{@$hS6*`kH@1d%Lo7fA#}N1)oN7`gm$~V
  z+wDx#)OFqMcE{s!JN0-xhG8ItAjVkJwEcb`3WWlJfU2r?;Pd%dmR+q@mSri5q9_W-
  zaR2~ECX?B2w+zELozC0s*6Z~|QG^f{3I#<`?)Q7U-JZ|q5W;9Q8i_=pBuSzunx=U;
  z9C)5jBoYw9^?EHyQl(M}1OlQcCX>lXB*ODN003Z&P17_@)3Pi=i0wb04<W?v-u}7K
  zXmmQA+wDgE!qR9o8jr`%=ab_&uh(l?R=r;Tjiqon91I2-hIu?57~@*4h7h9uORK#=
  gQItJW-{SoTm)8|5##k|m00000NkvXXu0mjf3JwksH2?qr
  


  $ hg diff --git -r 2 -r 3
  diff --git a/binfile.bin b/nonbinfile
  copy from binfile.bin
  copy to nonbinfile
  index 37ba3d1c6f17137d9c5f5776fa040caf5fe73ff9..8e27be7d6154a1f68ea9160ef0e18691d20560dc
  GIT binary patch
  literal 5
  Mc$_OqttjCF00uV!&;S4c
  
  $ cd ..

Test text mode with extended git-style diff format
  $ hg init b
  $ cd b
  $ cat > writebin.py <<EOF
  > import sys
  > path = sys.argv[1]
  > open(path, 'wb').write(b'\x00\x01\x02\x03')
  > EOF
  $ "$PYTHON" writebin.py binfile.bin
  $ hg add binfile.bin
  $ hg ci -m 'add binfile.bin'

  $ echo >> binfile.bin
  $ hg ci -m 'change binfile.bin'

  $ hg diff --git -a -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  --- a/binfile.bin
  +++ b/binfile.bin
  @@ -1,1 +1,1 @@
  -\x00\x01\x02\x03 (esc)
  \ No newline at end of file
  +\x00\x01\x02\x03 (esc)

  $ HGPLAIN=1 hg diff --git -a -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  --- a/binfile.bin
  +++ b/binfile.bin
  @@ -1,1 +1,1 @@
  -\x00\x01\x02\x03 (esc)
  \ No newline at end of file
  +\x00\x01\x02\x03 (esc)

Test binary mode with extended git-style diff format
  $ hg diff --no-binary -r 0 -r 1
  diff -r fb45f71337ad -r 9ca112d1a3c1 binfile.bin
  Binary file binfile.bin has changed

  $ hg diff --git --no-binary -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  Binary file binfile.bin has changed

  $ hg diff --git --binary -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  index eaf36c1daccfdf325514461cd1a2ffbc139b5464..ba71a782e93f3fb63a428383706065e3ec2828e9
  GIT binary patch
  literal 5
  Mc${NkWMbw50018V5dZ)H
  
  $ hg diff --git --binary --config diff.nobinary=True -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  index eaf36c1daccfdf325514461cd1a2ffbc139b5464..ba71a782e93f3fb63a428383706065e3ec2828e9
  GIT binary patch
  literal 5
  Mc${NkWMbw50018V5dZ)H
  

  $ hg diff --git --binary --text -r 0 -r 1
  diff --git a/binfile.bin b/binfile.bin
  --- a/binfile.bin
  +++ b/binfile.bin
  @@ -1,1 +1,1 @@
  -\x00\x01\x02\x03 (esc)
  \ No newline at end of file
  +\x00\x01\x02\x03 (esc)

  $ cd ..