view tests/test-flags.t @ 51108:0250e45040f1

revlog: add a small cache of unfiltered chunk

This can provides a massive boost to the reading of multiple revision and the
computation of a valid delta chain.

This greatly help operation like `hg log --patch`, delta computation (helping
pull/unbundle), linkrev adjustment (helping copy tracing).

A first round of benchmark for `hg log --patch --limit 1000` shows improvement
in the 10-20% range on "small" repository like pypy or mercurial and large
improvements (about 33%) for more complex ones like netbeans and mozilla's.

These speeds up are consistent with the improvement to `hg pull` (from a server
sending poor deltas) I saw benchmarking this last year. Further benchmark will
be run during the freeze.

I added some configuration in the experimental space to be able to further test
the effect of various tuning for now. This feature should fit well in the
"usage/resource profile" configuration that we should land next cycle.

When it does not provides a benefit the overhead of the cache seem to be around
2%, a small price for the big improvement. In addition I believe we could shave
most of this overhead with a more efficent lru implementation.

#require execbit

  $ umask 027

  $ hg init test1
  $ cd test1
  $ touch a b
  $ hg add a b
  $ hg ci -m "added a b"

  $ cd ..
  $ hg clone test1 test3
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg init test2
  $ cd test2
  $ hg pull ../test1
  pulling from ../test1
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 2 changes to 2 files
  new changesets 22a449e20da5
  (run 'hg update' to get a working copy)
  $ hg co
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ chmod +x a
  $ hg ci -m "chmod +x a"

the changelog should mention file a:

  $ hg tip --template '{files}\n'
  a

  $ cd ../test1
  $ echo 123 >>a
  $ hg ci -m "a updated"

  $ hg pull ../test2
  pulling from ../test2
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files (+1 heads)
  new changesets 7f4313b42a34
  1 local changesets published
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg heads
  changeset:   2:7f4313b42a34
  tag:         tip
  parent:      0:22a449e20da5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     chmod +x a
  
  changeset:   1:c6ecefc45368
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     a updated
  
  $ hg history
  changeset:   2:7f4313b42a34
  tag:         tip
  parent:      0:22a449e20da5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     chmod +x a
  
  changeset:   1:c6ecefc45368
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     a updated
  
  changeset:   0:22a449e20da5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     added a b
  

  $ hg -v merge
  resolving manifests
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ cat a
  123
  $ [ -x a ]

  $ cd ../test3
  $ echo 123 >>b
  $ hg ci -m "b updated"

  $ hg pull ../test2
  pulling from ../test2
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files (+1 heads)
  new changesets 7f4313b42a34
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg heads
  changeset:   2:7f4313b42a34
  tag:         tip
  parent:      0:22a449e20da5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     chmod +x a
  
  changeset:   1:dc57ead75f79
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     b updated
  
  $ hg history
  changeset:   2:7f4313b42a34
  tag:         tip
  parent:      0:22a449e20da5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     chmod +x a
  
  changeset:   1:dc57ead75f79
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     b updated
  
  changeset:   0:22a449e20da5
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     added a b
  

  $ hg -v merge
  resolving manifests
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

  $ ls -l ../test[123]/a > foo
  $ cut -b 1-10 < foo
  -rwxr-x---
  -rwxr-x---
  -rwxr-x---

  $ hg debugindex a
     rev linkrev       nodeid    p1-nodeid    p2-nodeid
       0       0 b80de5d13875 000000000000 000000000000
  $ hg debugindex -R ../test2 a
     rev linkrev       nodeid    p1-nodeid    p2-nodeid
       0       0 b80de5d13875 000000000000 000000000000
  $ hg debugindex -R ../test1 a
     rev linkrev       nodeid    p1-nodeid    p2-nodeid
       0       0 b80de5d13875 000000000000 000000000000
       1       1 7fe919cc0336 b80de5d13875 000000000000

  $ cd ..