view tests/test-rebase-scenario-global.t @ 26379:39d643252b9f

revlog: use existing file handle when reading during _addrevision

_addrevision() may need to read from revlogs as part of computing
deltas. Previously, we would flush existing file handles and open
a new, short-lived file handle to perform the reading.

If we have an existing file handle, it seems logical to reuse it
for reading instead of opening a new file handle. This patch
makes that the new behavior.

After this patch, revlog files are only reopened when adding
revisions if the revlog is switched from inline to non-inline.

On Linux when unbundling a bundle of the mozilla-central repo, this
patch has the following impact on system call counts:

Call     Before     After       Delta
write    827,639    673,390   -154,249
open     700,103    684,089    -16,014
read      74,489     74,489          0
fstat    493,924    461,896    -32,028
close    249,131    233,117    -16,014
stat     242,001    242,001          0
lstat     18,676     18,676          0
lseek     20,268     20,268          0
ioctl     14,652     13,173     -1,479
TOTAL  3,180,758  2,930,679   -250,079

It's worth noting that many of the open() calls fail due to missing
files. That's why there are many more open() calls than close().

Despite the significant system call reduction, this change does not
seem to have a significant performance impact on Linux.

On Windows 10 (not a VM, on a SSD), this patch appears to reduce
unbundle time for mozilla-central from ~960s to ~920s. This isn't
as significant as I was hoping. But a decrease it is nonetheless.
Still, Windows unbundle performance is still >2x slower than Linux.

Despite the lack of significant gains, fewer system calls is fewer
system calls. If nothing else, this will narrow the focus of potential
areas to optimize in the future.

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > rebase=
  > 
  > [phases]
  > publish=False
  > 
  > [alias]
  > tglog = log -G --template "{rev}: '{desc}' {branches}\n"
  > EOF


  $ hg init a
  $ cd a
  $ hg unbundle "$TESTDIR/bundles/rebase.hg"
  adding changesets
  adding manifests
  adding file changes
  added 8 changesets with 7 changes to 7 files (+2 heads)
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg up tip
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd ..


Rebasing
D onto H - simple rebase:
(this also tests that editor is invoked if '--edit' is specified)

  $ hg clone -q -u . a a1
  $ cd a1

  $ hg tglog
  @  7: 'H'
  |
  | o  6: 'G'
  |/|
  o |  5: 'F'
  | |
  | o  4: 'E'
  |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  

  $ hg status --rev "3^1" --rev 3
  A D
  $ HGEDITOR=cat hg rebase -s 3 -d 7 --edit
  rebasing 3:32af7686d403 "D"
  D
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: Nicolas Dumazet <[e-mail]>
  HG: branch 'default'
  HG: added D
  saved backup bundle to $TESTTMP/a1/.hg/strip-backup/32af7686d403-6f7dface-backup.hg (glob)

  $ hg tglog
  o  7: 'D'
  |
  @  6: 'H'
  |
  | o  5: 'G'
  |/|
  o |  4: 'F'
  | |
  | o  3: 'E'
  |/
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


D onto F - intermediate point:
(this also tests that editor is not invoked if '--edit' is not specified)

  $ hg clone -q -u . a a2
  $ cd a2

  $ HGEDITOR=cat hg rebase -s 3 -d 5
  rebasing 3:32af7686d403 "D"
  saved backup bundle to $TESTTMP/a2/.hg/strip-backup/32af7686d403-6f7dface-backup.hg (glob)

  $ hg tglog
  o  7: 'D'
  |
  | @  6: 'H'
  |/
  | o  5: 'G'
  |/|
  o |  4: 'F'
  | |
  | o  3: 'E'
  |/
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


E onto H - skip of G:

  $ hg clone -q -u . a a3
  $ cd a3

  $ hg rebase -s 4 -d 7
  rebasing 4:9520eea781bc "E"
  rebasing 6:eea13746799a "G"
  note: rebase of 6:eea13746799a created no changes to commit
  saved backup bundle to $TESTTMP/a3/.hg/strip-backup/9520eea781bc-fcd8edd4-backup.hg (glob)

  $ hg tglog
  o  6: 'E'
  |
  @  5: 'H'
  |
  o  4: 'F'
  |
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


F onto E - rebase of a branching point (skip G):

  $ hg clone -q -u . a a4
  $ cd a4

  $ hg rebase -s 5 -d 4
  rebasing 5:24b6387c8c8c "F"
  rebasing 6:eea13746799a "G"
  note: rebase of 6:eea13746799a created no changes to commit
  rebasing 7:02de42196ebe "H" (tip)
  saved backup bundle to $TESTTMP/a4/.hg/strip-backup/24b6387c8c8c-c3fe765d-backup.hg (glob)

  $ hg tglog
  @  6: 'H'
  |
  o  5: 'F'
  |
  o  4: 'E'
  |
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


G onto H - merged revision having a parent in ancestors of target:

  $ hg clone -q -u . a a5
  $ cd a5

  $ hg rebase -s 6 -d 7
  rebasing 6:eea13746799a "G"
  saved backup bundle to $TESTTMP/a5/.hg/strip-backup/eea13746799a-883828ed-backup.hg (glob)

  $ hg tglog
  o    7: 'G'
  |\
  | @  6: 'H'
  | |
  | o  5: 'F'
  | |
  o |  4: 'E'
  |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


F onto B - G maintains E as parent:

  $ hg clone -q -u . a a6
  $ cd a6

  $ hg rebase -s 5 -d 1
  rebasing 5:24b6387c8c8c "F"
  rebasing 6:eea13746799a "G"
  rebasing 7:02de42196ebe "H" (tip)
  saved backup bundle to $TESTTMP/a6/.hg/strip-backup/24b6387c8c8c-c3fe765d-backup.hg (glob)

  $ hg tglog
  @  7: 'H'
  |
  | o  6: 'G'
  |/|
  o |  5: 'F'
  | |
  | o  4: 'E'
  | |
  | | o  3: 'D'
  | | |
  +---o  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


These will fail (using --source):

G onto F - rebase onto an ancestor:

  $ hg clone -q -u . a a7
  $ cd a7

  $ hg rebase -s 6 -d 5
  nothing to rebase
  [1]

F onto G - rebase onto a descendant:

  $ hg rebase -s 5 -d 6
  abort: source is ancestor of destination
  [255]

G onto B - merge revision with both parents not in ancestors of target:

  $ hg rebase -s 6 -d 1
  rebasing 6:eea13746799a "G"
  abort: cannot use revision 6 as base, result would have 3 parents
  [255]


These will abort gracefully (using --base):

G onto G - rebase onto same changeset:

  $ hg rebase -b 6 -d 6
  nothing to rebase - eea13746799a is both "base" and destination
  [1]

G onto F - rebase onto an ancestor:

  $ hg rebase -b 6 -d 5
  nothing to rebase
  [1]

F onto G - rebase onto a descendant:

  $ hg rebase -b 5 -d 6
  nothing to rebase - "base" 24b6387c8c8c is already an ancestor of destination eea13746799a
  [1]

C onto A - rebase onto an ancestor:

  $ hg rebase -d 0 -s 2
  rebasing 2:5fddd98957c8 "C"
  rebasing 3:32af7686d403 "D"
  saved backup bundle to $TESTTMP/a7/.hg/strip-backup/5fddd98957c8-f9244fa1-backup.hg (glob)
  $ hg tglog
  o  7: 'D'
  |
  o  6: 'C'
  |
  | @  5: 'H'
  | |
  | | o  4: 'G'
  | |/|
  | o |  3: 'F'
  |/ /
  | o  2: 'E'
  |/
  | o  1: 'B'
  |/
  o  0: 'A'
  

Check rebasing public changeset

  $ hg pull --config phases.publish=True -q -r 6 . # update phase of 6
  $ hg rebase -d 0 -b 6
  nothing to rebase
  [1]
  $ hg rebase -d 5 -b 6
  abort: can't rebase public changeset e1c4361dd923
  (see "hg help phases" for details)
  [255]

  $ hg rebase -d 5 -b 6 --keep
  rebasing 6:e1c4361dd923 "C"
  rebasing 7:c9659aac0000 "D" (tip)

Check rebasing mutable changeset
Source phase greater or equal to destination phase: new changeset get the phase of source:
  $ hg id -n
  5
  $ hg rebase -s9 -d0
  rebasing 9:2b23e52411f4 "D" (tip)
  saved backup bundle to $TESTTMP/a7/.hg/strip-backup/2b23e52411f4-f942decf-backup.hg (glob)
  $ hg id -n # check we updated back to parent
  5
  $ hg log --template "{phase}\n" -r 9
  draft
  $ hg rebase -s9 -d1
  rebasing 9:2cb10d0cfc6c "D" (tip)
  saved backup bundle to $TESTTMP/a7/.hg/strip-backup/2cb10d0cfc6c-ddb0f256-backup.hg (glob)
  $ hg log --template "{phase}\n" -r 9
  draft
  $ hg phase --force --secret 9
  $ hg rebase -s9 -d0
  rebasing 9:c5b12b67163a "D" (tip)
  saved backup bundle to $TESTTMP/a7/.hg/strip-backup/c5b12b67163a-4e372053-backup.hg (glob)
  $ hg log --template "{phase}\n" -r 9
  secret
  $ hg rebase -s9 -d1
  rebasing 9:2a0524f868ac "D" (tip)
  saved backup bundle to $TESTTMP/a7/.hg/strip-backup/2a0524f868ac-cefd8574-backup.hg (glob)
  $ hg log --template "{phase}\n" -r 9
  secret
Source phase lower than destination phase: new changeset get the phase of destination:
  $ hg rebase -s8 -d9
  rebasing 8:6d4f22462821 "C"
  saved backup bundle to $TESTTMP/a7/.hg/strip-backup/6d4f22462821-3441f70b-backup.hg (glob)
  $ hg log --template "{phase}\n" -r 'rev(9)'
  secret

  $ cd ..

Test for revset

We need a bit different graph
All destination are B

  $ hg init ah
  $ cd ah
  $ hg unbundle "$TESTDIR/bundles/rebase-revset.hg"
  adding changesets
  adding manifests
  adding file changes
  added 9 changesets with 9 changes to 9 files (+2 heads)
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg tglog
  o  8: 'I'
  |
  o  7: 'H'
  |
  o  6: 'G'
  |
  | o  5: 'F'
  | |
  | o  4: 'E'
  |/
  o  3: 'D'
  |
  o  2: 'C'
  |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


Simple case with keep:

Source on have two descendant heads but ask for one

  $ hg clone -q -u . ah ah1
  $ cd ah1
  $ hg rebase -r '2::8' -d 1
  abort: can't remove original changesets with unrebased descendants
  (use --keep to keep original changesets)
  [255]
  $ hg rebase -r '2::8' -d 1 -k
  rebasing 2:c9e50f6cdc55 "C"
  rebasing 3:ffd453c31098 "D"
  rebasing 6:3d8a618087a7 "G"
  rebasing 7:72434a4e60b0 "H"
  rebasing 8:479ddb54a924 "I" (tip)
  $ hg tglog
  o  13: 'I'
  |
  o  12: 'H'
  |
  o  11: 'G'
  |
  o  10: 'D'
  |
  o  9: 'C'
  |
  | o  8: 'I'
  | |
  | o  7: 'H'
  | |
  | o  6: 'G'
  | |
  | | o  5: 'F'
  | | |
  | | o  4: 'E'
  | |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  

  $ cd ..

Base on have one descendant heads we ask for but common ancestor have two

  $ hg clone -q -u . ah ah2
  $ cd ah2
  $ hg rebase -r '3::8' -d 1
  abort: can't remove original changesets with unrebased descendants
  (use --keep to keep original changesets)
  [255]
  $ hg rebase -r '3::8' -d 1 --keep
  rebasing 3:ffd453c31098 "D"
  rebasing 6:3d8a618087a7 "G"
  rebasing 7:72434a4e60b0 "H"
  rebasing 8:479ddb54a924 "I" (tip)
  $ hg tglog
  o  12: 'I'
  |
  o  11: 'H'
  |
  o  10: 'G'
  |
  o  9: 'D'
  |
  | o  8: 'I'
  | |
  | o  7: 'H'
  | |
  | o  6: 'G'
  | |
  | | o  5: 'F'
  | | |
  | | o  4: 'E'
  | |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  

  $ cd ..

rebase subset

  $ hg clone -q -u . ah ah3
  $ cd ah3
  $ hg rebase -r '3::7' -d 1
  abort: can't remove original changesets with unrebased descendants
  (use --keep to keep original changesets)
  [255]
  $ hg rebase -r '3::7' -d 1 --keep
  rebasing 3:ffd453c31098 "D"
  rebasing 6:3d8a618087a7 "G"
  rebasing 7:72434a4e60b0 "H"
  $ hg tglog
  o  11: 'H'
  |
  o  10: 'G'
  |
  o  9: 'D'
  |
  | o  8: 'I'
  | |
  | o  7: 'H'
  | |
  | o  6: 'G'
  | |
  | | o  5: 'F'
  | | |
  | | o  4: 'E'
  | |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  

  $ cd ..

rebase subset with multiple head

  $ hg clone -q -u . ah ah4
  $ cd ah4
  $ hg rebase -r '3::(7+5)' -d 1
  abort: can't remove original changesets with unrebased descendants
  (use --keep to keep original changesets)
  [255]
  $ hg rebase -r '3::(7+5)' -d 1 --keep
  rebasing 3:ffd453c31098 "D"
  rebasing 4:c01897464e7f "E"
  rebasing 5:41bfcc75ed73 "F"
  rebasing 6:3d8a618087a7 "G"
  rebasing 7:72434a4e60b0 "H"
  $ hg tglog
  o  13: 'H'
  |
  o  12: 'G'
  |
  | o  11: 'F'
  | |
  | o  10: 'E'
  |/
  o  9: 'D'
  |
  | o  8: 'I'
  | |
  | o  7: 'H'
  | |
  | o  6: 'G'
  | |
  | | o  5: 'F'
  | | |
  | | o  4: 'E'
  | |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  

  $ cd ..

More advanced tests

rebase on ancestor with revset

  $ hg clone -q -u . ah ah5
  $ cd ah5
  $ hg rebase -r '6::' -d 2
  rebasing 6:3d8a618087a7 "G"
  rebasing 7:72434a4e60b0 "H"
  rebasing 8:479ddb54a924 "I" (tip)
  saved backup bundle to $TESTTMP/ah5/.hg/strip-backup/3d8a618087a7-b4f73f31-backup.hg (glob)
  $ hg tglog
  o  8: 'I'
  |
  o  7: 'H'
  |
  o  6: 'G'
  |
  | o  5: 'F'
  | |
  | o  4: 'E'
  | |
  | o  3: 'D'
  |/
  o  2: 'C'
  |
  | o  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..


rebase with multiple root.
We rebase E and G on B
We would expect heads are I, F if it was supported

  $ hg clone -q -u . ah ah6
  $ cd ah6
  $ hg rebase -r '(4+6)::' -d 1
  rebasing 4:c01897464e7f "E"
  rebasing 5:41bfcc75ed73 "F"
  rebasing 6:3d8a618087a7 "G"
  rebasing 7:72434a4e60b0 "H"
  rebasing 8:479ddb54a924 "I" (tip)
  saved backup bundle to $TESTTMP/ah6/.hg/strip-backup/3d8a618087a7-aae93a24-backup.hg (glob)
  $ hg tglog
  o  8: 'I'
  |
  o  7: 'H'
  |
  o  6: 'G'
  |
  | o  5: 'F'
  | |
  | o  4: 'E'
  |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  o |  1: 'B'
  |/
  o  0: 'A'
  
  $ cd ..

More complex rebase with multiple roots
each root have a different common ancestor with the destination and this is a detach

(setup)

  $ hg clone -q -u . a a8
  $ cd a8
  $ echo I > I
  $ hg add I
  $ hg commit -m I
  $ hg up 4
  1 files updated, 0 files merged, 3 files removed, 0 files unresolved
  $ echo I > J
  $ hg add J
  $ hg commit -m J
  created new head
  $ echo I > K
  $ hg add K
  $ hg commit -m K
  $ hg tglog
  @  10: 'K'
  |
  o  9: 'J'
  |
  | o  8: 'I'
  | |
  | o  7: 'H'
  | |
  +---o  6: 'G'
  | |/
  | o  5: 'F'
  | |
  o |  4: 'E'
  |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  
(actual test)

  $ hg rebase --dest 'desc(G)' --rev 'desc(K) + desc(I)'
  rebasing 8:e7ec4e813ba6 "I"
  rebasing 10:23a4ace37988 "K" (tip)
  saved backup bundle to $TESTTMP/a8/.hg/strip-backup/23a4ace37988-b06984b3-backup.hg (glob)
  $ hg log --rev 'children(desc(G))'
  changeset:   9:adb617877056
  parent:      6:eea13746799a
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     I
  
  changeset:   10:882431a34a0e
  tag:         tip
  parent:      6:eea13746799a
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     K
  
  $ hg tglog
  @  10: 'K'
  |
  | o  9: 'I'
  |/
  | o  8: 'J'
  | |
  | | o  7: 'H'
  | | |
  o---+  6: 'G'
  |/ /
  | o  5: 'F'
  | |
  o |  4: 'E'
  |/
  | o  3: 'D'
  | |
  | o  2: 'C'
  | |
  | o  1: 'B'
  |/
  o  0: 'A'
  

Test that rebase is not confused by $CWD disappearing during rebase (issue4121)

  $ cd ..
  $ hg init cwd-vanish
  $ cd cwd-vanish
  $ touch initial-file
  $ hg add initial-file
  $ hg commit -m 'initial commit'
  $ touch dest-file
  $ hg add dest-file
  $ hg commit -m 'dest commit'
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ touch other-file
  $ hg add other-file
  $ hg commit -m 'first source commit'
  created new head
  $ mkdir subdir
  $ cd subdir
  $ touch subfile
  $ hg add subfile
  $ hg commit -m 'second source with subdir'
  $ hg rebase -b . -d 1 --traceback
  rebasing 2:779a07b1b7a0 "first source commit"
  rebasing 3:a7d6f3a00bf3 "second source with subdir" (tip)
  saved backup bundle to $TESTTMP/cwd-vanish/.hg/strip-backup/779a07b1b7a0-853e0073-backup.hg (glob)