view tests/test-repo-filters-tiptoe.t @ 49622:dcb2581e33be stable

memory-usage: fix `hg log --follow --rev R F` space complexity

When running `hg log --follow --rev REVS FILES`, the log code will walk the
history of all FILES starting from the file revisions that exists in each REVS.

Before doing so, it looks if the files actually exists in the target revisions.
To do so, it opens the manifest of each revision in REVS to look up if we find
the associated items in FILES.

Before this changeset this was done in a way that created a changectx for
each target revision, keeping them in memory while we look into each file.

If the set of REVS is large, this means keeping the manifest for each entry in
REVS in memory. That can be large… if REV is in the form `::X`, this can quickly
become huge and saturate the memory. We have seen usage allocating 2GB per
second until memory runs out.

So this changeset invert the two loop so that only one revision is kept in
memory during the operation. This solve the memory explosion issue.

===================================
Test repository filtering avoidance
===================================

This test file is a bit special as he does not check feature, but performance related internal code path.

Right now, filtering a repository comes with a cost that might be significant.
Until this get better, ther are various operation that try hard not to trigger
a filtering computation. This test file make sure we don't reintroduce code that trigger the filtering for these operation:

Setup
-----
  $ hg init test-repo
  $ cd test-repo
  $ echo "some line" > z
  $ echo a > a
  $ hg commit -Am a
  adding a
  adding z
  $ echo "in a" >> z
  $ echo b > b
  $ hg commit -Am b
  adding b
  $ echo "file" >> z
  $ echo c > c
  $ hg commit -Am c
  adding c
  $ hg rm a
  $ echo c1 > c
  $ hg add c
  c already tracked!
  $ echo d > d
  $ hg add d
  $ rm b

  $ cat << EOF >> $HGRCPATH
  > [devel]
  > debug.repo-filters = yes
  > [ui]
  > debug = yes
  > EOF


tests
-----

Getting the node of `null`

  $ hg log -r null -T "{node}\n"
  0000000000000000000000000000000000000000

Getting basic changeset inforation about `null`

  $ hg log -r null -T "{node}\n{date}\n"
  0000000000000000000000000000000000000000
  0.00

Getting status of null

  $ hg status --change null

Getting status of working copy

  $ hg status
  M c
  A d
  R a
  ! b

  $ hg status --copies
  M c
  A d
  R a
  ! b

Getting data about the working copy parent

  $ hg log -r '.' -T "{node}\n{date}\n"
  c2932ca7786be30b67154d541a8764fae5532261
  0.00

Getting working copy diff

  $ hg diff
  diff -r c2932ca7786be30b67154d541a8764fae5532261 a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +0,0 @@
  -a
  diff -r c2932ca7786be30b67154d541a8764fae5532261 c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -c
  +c1
  diff -r c2932ca7786be30b67154d541a8764fae5532261 d
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/d	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +d
  $ hg diff --change .
  diff -r 05293e5dd8d1ae4f84a8520a11c6f97cad26deca -r c2932ca7786be30b67154d541a8764fae5532261 c
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +c
  diff -r 05293e5dd8d1ae4f84a8520a11c6f97cad26deca -r c2932ca7786be30b67154d541a8764fae5532261 z
  --- a/z	Thu Jan 01 00:00:00 1970 +0000
  +++ b/z	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,2 +1,3 @@
   some line
   in a
  +file

exporting the current changeset

  $ hg export
  exporting patch:
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID c2932ca7786be30b67154d541a8764fae5532261
  # Parent  05293e5dd8d1ae4f84a8520a11c6f97cad26deca
  c
  
  diff -r 05293e5dd8d1ae4f84a8520a11c6f97cad26deca -r c2932ca7786be30b67154d541a8764fae5532261 c
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +c
  diff -r 05293e5dd8d1ae4f84a8520a11c6f97cad26deca -r c2932ca7786be30b67154d541a8764fae5532261 z
  --- a/z	Thu Jan 01 00:00:00 1970 +0000
  +++ b/z	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,2 +1,3 @@
   some line
   in a
  +file

using annotate

- file with a single change

  $ hg annotate a
  0: a

- file with multiple change

  $ hg annotate z
  0: some line
  1: in a
  2: file