view tests/test-notify-changegroup.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 <<EOF >> $HGRCPATH
  > [extensions]
  > notify=
  > 
  > [hooks]
  > changegroup.notify = python:hgext.notify.hook
  > 
  > [notify]
  > sources = push
  > diffstat = False
  > maxsubject = 10
  > 
  > [usersubs]
  > foo@bar = *
  > 
  > [reposubs]
  > * = baz
  > EOF
  $ hg init a

clone

  $ hg --traceback clone a b
  updating to branch default
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo a > b/a

commit

  $ hg --traceback --cwd b commit -Ama
  adding a
  $ echo a >> b/a

commit

  $ hg --traceback --cwd b commit -Amb

push

  $ hg --traceback --cwd b push ../a 2>&1 |
  >     $PYTHON -c 'import sys,re; print re.sub("\n\t", " ", sys.stdin.read()),'
  pushing to ../a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  Content-Type: text/plain; charset="us-ascii"
  MIME-Version: 1.0
  Content-Transfer-Encoding: 7bit
  Date: * (glob)
  Subject: * (glob)
  From: test
  X-Hg-Notification: changeset cb9a9f314b8b
  Message-Id: <*> (glob)
  To: baz, foo@bar
  
  changeset cb9a9f314b8b in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=cb9a9f314b8b
  summary: a
  
  changeset ba677d0156c1 in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=ba677d0156c1
  summary: b
  
  diffs (6 lines):
  
  diff -r 000000000000 -r ba677d0156c1 a
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,2 @@
  +a
  +a
  $ hg --cwd a rollback
  repository tip rolled back to revision -1 (undo push)

unbundle with unrelated source

  $ hg --cwd b bundle ../test.hg ../a
  searching for changes
  2 changesets found
  $ hg --cwd a unbundle ../test.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  (run 'hg update' to get a working copy)
  $ hg --cwd a rollback
  repository tip rolled back to revision -1 (undo unbundle)

unbundle with correct source

  $ hg --config notify.sources=unbundle --cwd a unbundle ../test.hg 2>&1 |
  >     $PYTHON -c 'import sys,re; print re.sub("\n\t", " ", sys.stdin.read()),'
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  Content-Type: text/plain; charset="us-ascii"
  MIME-Version: 1.0
  Content-Transfer-Encoding: 7bit
  Date: * (glob)
  Subject: * (glob)
  From: test
  X-Hg-Notification: changeset cb9a9f314b8b
  Message-Id: <*> (glob)
  To: baz, foo@bar
  
  changeset cb9a9f314b8b in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=cb9a9f314b8b
  summary: a
  
  changeset ba677d0156c1 in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=ba677d0156c1
  summary: b
  
  diffs (6 lines):
  
  diff -r 000000000000 -r ba677d0156c1 a
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,2 @@
  +a
  +a
  (run 'hg update' to get a working copy)

Check that using the first committer as the author of a changeset works:
Check that the config option works.
Check that the first committer is indeed used for "From:".
Check that the merge user is NOT used for "From:"

Create new file

  $ echo a > b/b
  $ echo b >> b/b
  $ echo c >> b/b
  $ hg --traceback --cwd b commit -Amnewfile -u committer_1
  adding b

commit as one user

  $ echo x > b/b
  $ echo b >> b/b
  $ echo c >> b/b
  $ hg --traceback --cwd b commit -Amx -u committer_2

commit as other user, change file so we can do an (automatic) merge

  $ hg --cwd b up 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo a > b/b
  $ echo b >> b/b
  $ echo y >> b/b
  $ hg --traceback --cwd b commit -Amy -u committer_3
  created new head

merge as a different user

  $ hg --cwd b merge --config notify.fromauthor=True
  merging b
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ hg --traceback --cwd b commit -Am "merged"

push

  $ hg --traceback --cwd b --config notify.fromauthor=True push ../a 2>&1 |
  >     $PYTHON -c 'import sys,re; print re.sub("\n\t", " ", sys.stdin.read()),'
  pushing to ../a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 4 changesets with 4 changes to 1 files
  Content-Type: text/plain; charset="us-ascii"
  MIME-Version: 1.0
  Content-Transfer-Encoding: 7bit
  Date: * (glob)
  Subject: * (glob)
  From: committer_1
  X-Hg-Notification: changeset 84e487dddc58
  Message-Id: <*> (glob)
  To: baz, foo@bar
  
  changeset 84e487dddc58 in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=84e487dddc58
  summary: newfile
  
  changeset b29c7a2b6b0c in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=b29c7a2b6b0c
  summary: x
  
  changeset 0957c7d64886 in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=0957c7d64886
  summary: y
  
  changeset 485b4e6b0249 in $TESTTMP/a (glob)
  details: $TESTTMP/a?cmd=changeset;node=485b4e6b0249
  summary: merged
  
  diffs (7 lines):
  
  diff -r ba677d0156c1 -r 485b4e6b0249 b
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,3 @@
  +x
  +b
  +y
  $ hg --cwd a rollback
  repository tip rolled back to revision 1 (undo push)