view tests/test-remotefilelog-linknodes.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
author Pierre-Yves David <pierre-yves.david@octobus.net>
date Tue, 11 Feb 2020 11:18:52 +0100
parents 4edd427f34c1
children f90a5c211251
line wrap: on
line source

#require no-windows

# Tests for the complicated linknode logic in remotefilelog.py::ancestormap()

  $ . "$TESTDIR/remotefilelog-library.sh"

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > serverexpiration=-1
  > EOF
  $ echo x > x
  $ hg commit -qAm x
  $ cd ..

  $ hgcloneshallow ssh://user@dummy/master shallow -q
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)

# Rebase produces correct log -f linknodes

  $ cd shallow
  $ echo y > y
  $ hg commit -qAm y
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo x >> x
  $ hg commit -qAm xx
  $ hg log -f x --template "{node|short}\n"
  0632994590a8
  b292c1e3311f

  $ hg rebase -d 1
  rebasing 2:0632994590a8 "xx" (tip)
  saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/0632994590a8-0bc786d8-rebase.hg (glob)
  $ hg log -f x --template "{node|short}\n"
  81deab2073bc
  b292c1e3311f

# Rebase back, log -f still works

  $ hg rebase -d 0 -r 2
  rebasing 2:81deab2073bc "xx" (tip)
  saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/81deab2073bc-80cb4fda-rebase.hg (glob)
  $ hg log -f x --template "{node|short}\n"
  b3fca10fb42d
  b292c1e3311f

  $ hg rebase -d 1 -r 2
  rebasing 2:b3fca10fb42d "xx" (tip)
  saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/b3fca10fb42d-da73a0c7-rebase.hg (glob)

  $ cd ..

# Reset repos
  $ clearcache

  $ rm -rf master
  $ rm -rf shallow
  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > serverexpiration=-1
  > EOF
  $ echo x > x
  $ hg commit -qAm x
  $ cd ..

  $ hgcloneshallow ssh://user@dummy/master shallow -q
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)

# Rebase stack onto landed commit

  $ cd master
  $ echo x >> x
  $ hg commit -Aqm xx

  $ cd ../shallow
  $ echo x >> x
  $ hg commit -Aqm xx2
  $ echo y >> x
  $ hg commit -Aqm xxy

  $ hg pull -q
  $ hg rebase -d tip
  rebasing 1:4549721d828f "xx2"
  note: not rebasing 1:4549721d828f "xx2", its destination already has all its changes
  rebasing 2:5ef6d97e851c "xxy"
  saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/4549721d828f-b084e33c-rebase.hg (glob)
  $ hg log -f x --template '{node|short}\n'
  4ae8e31c85ef
  0632994590a8
  b292c1e3311f

  $ cd ..

# system cache has invalid linknode, but .hg/store/data has valid

  $ cd shallow
  $ hg strip -r 1 -q
  $ rm -rf .hg/store/data/*
  $ echo x >> x
  $ hg commit -Aqm xx_local
  $ hg log -f x --template '{rev}:{node|short}\n'
  1:21847713771d
  0:b292c1e3311f

  $ cd ..
  $ rm -rf shallow

/* Local linknode is invalid; remote linknode is valid (formerly slow case) */

  $ hgcloneshallow ssh://user@dummy/master shallow -q
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
  $ cd shallow
  $ echo x >> x
  $ hg commit -Aqm xx2
  $ cd ../master
  $ echo y >> y
  $ hg commit -Aqm yy2
  $ echo x >> x
  $ hg commit -Aqm xx2-fake-rebased
  $ echo y >> y
  $ hg commit -Aqm yy3
  $ cd ../shallow
  $ hg pull --config remotefilelog.debug=True
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 0 changes to 0 files (+1 heads)
  new changesets 01979f9404f8:7200df4e0aca
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg update tip -q
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
  $ echo x > x
  $ hg commit -qAm xx3

# At this point, the linknode points to c1254e70bad1 instead of 32e6611f6149
  $ hg log -G -T '{node|short} {desc} {phase} {files}\n'
  @  a5957b6bf0bd xx3 draft x
  |
  o  7200df4e0aca yy3 public y
  |
  o  32e6611f6149 xx2-fake-rebased public x
  |
  o  01979f9404f8 yy2 public y
  |
  | o  c1254e70bad1 xx2 draft x
  |/
  o  0632994590a8 xx public x
  |
  o  b292c1e3311f x public x
  
# Check the contents of the local blob for incorrect linknode
  $ hg debugremotefilelog .hg/store/data/11f6ad8ec52a2984abaafd7c3b516503785c2072/d4a3ed9310e5bd9887e3bf779da5077efab28216
  size: 6 bytes
  path: .hg/store/data/11f6ad8ec52a2984abaafd7c3b516503785c2072/d4a3ed9310e5bd9887e3bf779da5077efab28216 
  key: d4a3ed9310e5 
  
          node =>           p1            p2      linknode     copyfrom
  d4a3ed9310e5 => aee31534993a  000000000000  c1254e70bad1  
  aee31534993a => 1406e7411862  000000000000  0632994590a8  
  1406e7411862 => 000000000000  000000000000  b292c1e3311f  

# Verify that we do a fetch on the first log (remote blob fetch for linkrev fix)
  $ hg log -f x -T '{node|short} {desc} {phase} {files}\n'
  a5957b6bf0bd xx3 draft x
  32e6611f6149 xx2-fake-rebased public x
  0632994590a8 xx public x
  b292c1e3311f x public x
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)

# But not after that
  $ hg log -f x -T '{node|short} {desc} {phase} {files}\n'
  a5957b6bf0bd xx3 draft x
  32e6611f6149 xx2-fake-rebased public x
  0632994590a8 xx public x
  b292c1e3311f x public x

# Check the contents of the remote blob for correct linknode
  $ hg debugremotefilelog $CACHEDIR/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/d4a3ed9310e5bd9887e3bf779da5077efab28216
  size: 6 bytes
  path: $TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/d4a3ed9310e5bd9887e3bf779da5077efab28216 
  key: d4a3ed9310e5 
  
          node =>           p1            p2      linknode     copyfrom
  d4a3ed9310e5 => aee31534993a  000000000000  32e6611f6149  
  aee31534993a => 1406e7411862  000000000000  0632994590a8  
  1406e7411862 => 000000000000  000000000000  b292c1e3311f