view tests/test-identify.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

#require serve

#if no-outer-repo

no repo

  $ hg id
  abort: there is no Mercurial repository here (.hg not found)
  [255]

#endif

create repo

  $ hg init test
  $ cd test
  $ echo a > a
  $ hg ci -Ama
  adding a

basic id usage

  $ hg id
  cb9a9f314b8b tip
  $ hg id --debug
  cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b tip
  $ hg id -q
  cb9a9f314b8b
  $ hg id -v
  cb9a9f314b8b tip

with options

  $ hg id -r.
  cb9a9f314b8b tip
  $ hg id -n
  0
  $ hg id -t
  tip
  $ hg id -b
  default
  $ hg id -i
  cb9a9f314b8b
  $ hg id -n -t -b -i
  cb9a9f314b8b 0 default tip
  $ hg id -Tjson
  [
   {
    "bookmarks": [],
    "branch": "default",
    "dirty": "",
    "id": "cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b",
    "node": "ffffffffffffffffffffffffffffffffffffffff",
    "parents": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"],
    "tags": ["tip"]
   }
  ]

test template keywords and functions which require changectx:

  $ hg id -T '{rev} {node|shortest}\n'
  2147483647 ffff
  $ hg id -T '{parents % "{rev} {node|shortest} {desc}\n"}'
  0 cb9a a
  $ hg id -T '{parents}\n'
  cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b

test nested template: '{tags}'/'{node}' constants shouldn't override the
default keywords, but '{id}' persists because there's no default keyword
for '{id}' (issue5612)

  $ hg id -T '{tags}\n'
  tip
  $ hg id -T '{revset("null:.") % "{rev}:{node|short} {tags} {id|short}\n"}'
  -1:000000000000  cb9a9f314b8b
  0:cb9a9f314b8b tip cb9a9f314b8b

with modifications

  $ echo b > a
  $ hg id -n -t -b -i
  cb9a9f314b8b+ 0+ default tip
  $ hg id -Tjson
  [
   {
    "bookmarks": [],
    "branch": "default",
    "dirty": "+",
    "id": "cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b+",
    "node": "ffffffffffffffffffffffffffffffffffffffff",
    "parents": ["cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b"],
    "tags": ["tip"]
   }
  ]

other local repo

  $ cd ..
  $ hg -R test id
  cb9a9f314b8b+ tip
#if no-outer-repo
  $ hg id test
  cb9a9f314b8b+ tip
#endif

with remote http repo

  $ cd test
  $ hg serve -p $HGPORT1 -d --pid-file=hg.pid
  $ cat hg.pid >> $DAEMON_PIDS
  $ hg id http://localhost:$HGPORT1/
  cb9a9f314b8b

remote with rev number?

  $ hg id -n http://localhost:$HGPORT1/
  abort: can't query remote revision number, branch, or tags
  [255]

remote with tags?

  $ hg id -t http://localhost:$HGPORT1/
  abort: can't query remote revision number, branch, or tags
  [255]

remote with branch?

  $ hg id -b http://localhost:$HGPORT1/
  abort: can't query remote revision number, branch, or tags
  [255]

test bookmark support

  $ hg bookmark Y
  $ hg bookmark Z
  $ hg bookmarks
     Y                         0:cb9a9f314b8b
   * Z                         0:cb9a9f314b8b
  $ hg id
  cb9a9f314b8b+ tip Y/Z
  $ hg id --bookmarks
  Y Z

test remote identify with bookmarks

  $ hg id http://localhost:$HGPORT1/
  cb9a9f314b8b Y/Z
  $ hg id --bookmarks http://localhost:$HGPORT1/
  Y Z
  $ hg id -r . http://localhost:$HGPORT1/
  cb9a9f314b8b Y/Z
  $ hg id --bookmarks -r . http://localhost:$HGPORT1/
  Y Z

test invalid lookup

  $ hg id -r noNoNO http://localhost:$HGPORT1/
  abort: unknown revision 'noNoNO'!
  [255]

Make sure we do not obscure unknown requires file entries (issue2649)

  $ echo fake >> .hg/requires
  $ hg id
  abort: repository requires features unknown to this Mercurial: fake!
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]

  $ cd ..
#if no-outer-repo
  $ hg id test
  abort: repository requires features unknown to this Mercurial: fake!
  (see https://mercurial-scm.org/wiki/MissingRequirement for more information)
  [255]
#endif