Patchwork D9300: copies-rust: use immutable "OrdMap" to store copies information

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Date Nov. 12, 2020, 3:16 p.m.
Message ID <differential-rev-PHID-DREV-7ovmqh564letdfelsffv-req@mercurial-scm.org>
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Permalink /patch/47576/
State Superseded
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phabricator - Nov. 12, 2020, 3:16 p.m.
marmoute created this revision.
Herald added a reviewer: hg-reviewers.
Herald added a subscriber: mercurial-patches.

REVISION SUMMARY
  The large majority of time is currently spent coping and merging directories.
  the `IM` crate offer "immutable" Map, that use "copy on write" internally.  The
  new object use the same API as the standard HashMap.  So switching to it is
  trivial and it reduce copying cost significantly. More importantly, using
  immutable structure will unlock new possibility for a massive speed up of the
  "merging" part. This will came in a later changesets.
  
  Performance wise, we get very significant boost in the worst case. Below is some
  highlight of how we fare compared to the previous changeset.
  
  Repo            Cases                                 Source-Rev   Dest-Rev         Old-Time      New-Time     Difference   Factor
  ----------------------------------------------------------------------------------------------------------------------------------
  
  pypy            x0000_revs_x_added_0_copies           d1defd0dc478 c9cb1334cc78 :  62.468362 s,  33.527067 s, -28.941295 s, × 0.5367
  mozilla-central x000_revs_x000_added_x000_copies      7c97034feb78 4407bd0c6330 :   3.619850 s,   0.963905 s,  -2.655945 s, × 0.2663
  mozilla-central x0000_revs_xx000_added_x000_copies    f78c615a656c 96a38b690156 :  11.926587 s,   4.217003 s,  -7.709584 s, × 0.3536
  mozilla-try     x0000_revs_x_added_0_copies           63519bfd42ee a36a2a865d92 :  10.674920 s,   1.114864 s,  -9.560056 s, × 0.1044
  mozilla-try     x00000_revs_x00000_added_0_copies     dc8a3ca7010e d16fde900c9c :  19.647038 s,   1.442793 s, -18.204245 s, × 0.0734
  
  And we sometimes catch up with the performance of the python code as highlighted
  below:
  
  Repo            Cases                                 Source-Rev   Dest-Rev         Py-time       Rust-time    Difference   Factor
  ----------------------------------------------------------------------------------------------------------------------------------
  
  mozilla-try     x00000_revs_x00000_added_0_copies     dc8a3ca7010e d16fde900c9c :   1.074593 s,   1.442793 s,  +0.368200 s, × 1.3426
  
  However, multiple case remains significantly slower, as highlighted below
  
  Repo            Cases                                 Source-Rev   Dest-Rev         Py-time       Rust-time    Difference   Factor
  ----------------------------------------------------------------------------------------------------------------------------------
  
  mozilla-central x000_revs_x000_added_x000_copies      7c97034feb78 4407bd0c6330 :   0.190133 s,   0.963905 s,  +0.773772 s, × 5.0696
  mozilla-central x0000_revs_xx000_added_x000_copies    f78c615a656c 96a38b690156 :   0.440694 s,   4.217003 s,  +3.776309 s, × 9.5690
  mozilla-try     x0000_revs_x_added_0_copies           63519bfd42ee a36a2a865d92 :   0.370675 s,   1.114864 s,  +0.744189 s, × 3.0077
  pypy            x0000_revs_x_added_0_copies           d1defd0dc478 c9cb1334cc78 :   3.581556 s,  33.527067 s, +29.945511 s, × 9.3610
  
  Below are two different tables for full performance comparison
  
  - this changeset against the previous one (spoiler: it is much better)
  - this changeset against the python code  (spoiler: still slower, but it gets more comparable)
  
  This changeset compared to the previous one
  ===========================================
  
  Repo            Cases                                 Source-Rev   Dest-Rev         Old-Time      New-Time     Difference   Factor
  ----------------------------------------------------------------------------------------------------------------------------------
  
  mercurial       x_revs_x_added_0_copies               ad6b123de1c7 <https://phab.mercurial-scm.org/rHGad6b123de1c7868a4be537a0e3fa5eb6a962dd3b> 39cfcef4f463 <https://phab.mercurial-scm.org/rHG39cfcef4f46358a25ebf32670191687826ca2bdf> :   0.000046 s,   0.000049 s,  +0.000003 s, × 1.0652
  mercurial       x_revs_x_added_x_copies               2b1c78674230 <https://phab.mercurial-scm.org/rHG2b1c786742301bb757226a898fafe595a90462fb> 0c1d10351869 <https://phab.mercurial-scm.org/rHG0c1d103518698454c9a8825b66276becf2820f86> :   0.000173 s,   0.000179 s,  +0.000006 s, × 1.0347
  mercurial       x000_revs_x000_added_x_copies         81f8ff2a9bf2 <https://phab.mercurial-scm.org/rHG81f8ff2a9bf20606fc89bc787983f592183e25b5> dd3267698d84 <https://phab.mercurial-scm.org/rHGdd3267698d84458686b3c5682ce027438900ffbd> :   0.006303 s,   0.006494 s,  +0.000191 s, × 1.0303
  pypy            x_revs_x_added_0_copies               aed021ee8ae8 099ed31b181b :   0.000229 s,   0.000339 s,  +0.000110 s, × 1.4803
  pypy            x_revs_x000_added_0_copies            4aa4e1f8e19a 359343b9ac0e :   0.000056 s,   0.000057 s,  +0.000001 s, × 1.0179
  pypy            x_revs_x_added_x_copies               ac52eb7bbbb0 72e022663155 :   0.000143 s,   0.000299 s,  +0.000156 s, × 2.0909
  pypy            x_revs_x00_added_x_copies             c3b14617fbd7 ace7255d9a26 :   0.001166 s,   0.001200 s,  +0.000034 s, × 1.0292
  pypy            x_revs_x000_added_x000_copies         df6f7a526b60 a83dc6a2d56f :   0.022931 s,   0.025120 s,  +0.002189 s, × 1.0955
  pypy            x000_revs_xx00_added_0_copies         89a76aede314 2f22446ff07e :   0.852446 s,   0.506921 s,  -0.345525 s, × 0.5947
  pypy            x000_revs_x000_added_x_copies         8a3b5bfd266e 2c68e87c3efe :   2.221824 s,   1.272060 s,  -0.949764 s, × 0.5725
  pypy            x000_revs_x000_added_x000_copies      89a76aede314 7b3dda341c84 :   1.194162 s,   0.690941 s,  -0.503221 s, × 0.5786
  pypy            x0000_revs_x_added_0_copies           d1defd0dc478 c9cb1334cc78 :  62.468362 s,  33.527067 s, -28.941295 s, × 0.5367
  pypy            x0000_revs_xx000_added_0_copies       bf2c629d0071 4ffed77c095c :   0.022116 s,   0.021970 s,  -0.000146 s, × 0.9934
  pypy            x0000_revs_xx000_added_x000_copies    08ea3258278e d9fa043f30c0 :   2.972788 s,   1.772094 s,  -1.200694 s, × 0.5961
  netbeans        x_revs_x_added_0_copies               fb0955ffcbcd a01e9239f9e7 :   0.000180 s,   0.000185 s,  +0.000005 s, × 1.0278
  netbeans        x_revs_x000_added_0_copies            6f360122949f 20eb231cc7d0 :   0.000123 s,   0.000135 s,  +0.000012 s, × 1.0976
  netbeans        x_revs_x_added_x_copies               1ada3faf6fb6 5a39d12eecf4 :   0.000315 s,   0.000329 s,  +0.000014 s, × 1.0444
  netbeans        x_revs_x00_added_x_copies             35be93ba1e2c 9eec5e90c05f :   0.001297 s,   0.001343 s,  +0.000046 s, × 1.0355
  netbeans        x000_revs_xx00_added_0_copies         eac3045b4fdd 51d4ae7f1290 :   0.024884 s,   0.029396 s,  +0.004512 s, × 1.1813
  netbeans        x000_revs_x000_added_x_copies         e2063d266acd 6081d72689dc :   0.032653 s,   0.040210 s,  +0.007557 s, × 1.2314
  netbeans        x000_revs_x000_added_x000_copies      ff453e9fee32 411350406ec2 :   4.230118 s,   4.556794 s,  +0.326676 s, × 1.0772
  mozilla-central x_revs_x_added_0_copies               3697f962bb7b 7015fcdd43a2 :   0.000197 s,   0.000199 s,  +0.000002 s, × 1.0102
  mozilla-central x_revs_x000_added_0_copies            dd390860c6c9 40d0c5bed75d :   0.000622 s,   0.000639 s,  +0.000017 s, × 1.0273
  mozilla-central x_revs_x_added_x_copies               8d198483ae3b 14207ffc2b2f :   0.000296 s,   0.000542 s,  +0.000246 s, × 1.8311
  mozilla-central x_revs_x00_added_x_copies             98cbc58cc6bc 446a150332c3 :   0.001626 s,   0.001685 s,  +0.000059 s, × 1.0363
  mozilla-central x_revs_x000_added_x000_copies         3c684b4b8f68 0a5e72d1b479 :   0.006218 s,   0.006954 s,  +0.000736 s, × 1.1184
  mozilla-central x_revs_x0000_added_x0000_copies       effb563bb7e5 c07a39dc4e80 :   0.132760 s,   0.132938 s,  +0.000178 s, × 1.0013
  mozilla-central x000_revs_xx00_added_0_copies         6100d773079a 04a55431795e :   0.029001 s,   0.008683 s,  -0.020318 s, × 0.2994
  mozilla-central x000_revs_x000_added_x_copies         9f17a6fc04f9 2d37b966abed :   0.005886 s,   0.005956 s,  +0.000070 s, × 1.0119
  mozilla-central x000_revs_x000_added_x000_copies      7c97034feb78 4407bd0c6330 :   3.619850 s,   0.963905 s,  -2.655945 s, × 0.2663
  mozilla-central x0000_revs_xx000_added_0_copies       9eec5917337d 67118cc6dcad :   0.058678 s,   0.049239 s,  -0.009439 s, × 0.8391
  mozilla-central x0000_revs_xx000_added_x000_copies    f78c615a656c 96a38b690156 :  11.926587 s,   4.217003 s,  -7.709584 s, × 0.3536
  mozilla-try     x_revs_x_added_0_copies               aaf6dde0deb8 9790f499805a :   0.001204 s,   0.001197 s,  -0.000007 s, × 0.9942
  mozilla-try     x_revs_x000_added_0_copies            d8d0222927b4 5bb8ce8c7450 :   0.001217 s,   0.001213 s,  -0.000004 s, × 0.9967
  mozilla-try     x_revs_x_added_x_copies               092fcca11bdb 936255a0384a :   0.000605 s,   0.000762 s,  +0.000157 s, × 1.2595
  mozilla-try     x_revs_x00_added_x_copies             b53d2fadbdb5 017afae788ec :   0.001876 s,   0.001909 s,  +0.000033 s, × 1.0176
  mozilla-try     x_revs_x000_added_x000_copies         20408ad61ce5 6f0ee96e21ad :   0.078190 s,   0.093021 s,  +0.014831 s, × 1.1897
  mozilla-try     x_revs_x0000_added_x0000_copies       effb563bb7e5 c07a39dc4e80 :   0.135428 s,   0.134536 s,  -0.000892 s, × 0.9934
  mozilla-try     x000_revs_xx00_added_0_copies         6100d773079a 04a55431795e :   0.029123 s,   0.009071 s,  -0.020052 s, × 0.3115
  mozilla-try     x000_revs_x000_added_x_copies         9f17a6fc04f9 2d37b966abed :   0.006141 s,   0.006206 s,  +0.000065 s, × 1.0106
  mozilla-try     x000_revs_x000_added_x000_copies      1346fd0130e4 4c65cbdabc1f :   4.857827 s,   1.150502 s,  -3.707325 s, × 0.2368
  mozilla-try     x0000_revs_x_added_0_copies           63519bfd42ee a36a2a865d92 :  10.674920 s,   1.114864 s,  -9.560056 s, × 0.1044
  mozilla-try     x0000_revs_x_added_x_copies           9fe69ff0762d bcabf2a78927 :   9.789462 s,   1.042658 s,  -8.746804 s, × 0.1065
  mozilla-try     x0000_revs_xx000_added_x_copies       156f6e2674f2 4d0f2c178e66 :   1.087890 s,   0.447402 s,  -0.640488 s, × 0.4113
  mozilla-try     x0000_revs_xx000_added_0_copies       9eec5917337d 67118cc6dcad :   0.060556 s,   0.051132 s,  -0.009424 s, × 0.8444
  mozilla-try     x0000_revs_xx000_added_x000_copies    89294cd501d9 7ccb2fc7ccb5 : killed         ,  83.508590 s
  mozilla-try     x0000_revs_x0000_added_x0000_copies   e928c65095ed e951f4ad123a : killed         ,  55.079813 s
  mozilla-try     x00000_revs_x00000_added_0_copies     dc8a3ca7010e d16fde900c9c :  19.647038 s,   1.442793 s, -18.204245 s, × 0.0734
  
  This changeset compared to the Python Code
  ==========================================
  
  Repo            Cases                                 Source-Rev   Dest-Rev         Py-time       Rust-time    Difference   Factor
  ----------------------------------------------------------------------------------------------------------------------------------
  
  mercurial       x_revs_x_added_0_copies               ad6b123de1c7 <https://phab.mercurial-scm.org/rHGad6b123de1c7868a4be537a0e3fa5eb6a962dd3b> 39cfcef4f463 <https://phab.mercurial-scm.org/rHG39cfcef4f46358a25ebf32670191687826ca2bdf> :   0.000044 s,   0.000049 s,  +0.000005 s, × 1.1136
  mercurial       x_revs_x_added_x_copies               2b1c78674230 <https://phab.mercurial-scm.org/rHG2b1c786742301bb757226a898fafe595a90462fb> 0c1d10351869 <https://phab.mercurial-scm.org/rHG0c1d103518698454c9a8825b66276becf2820f86> :   0.000138 s,   0.000179 s,  +0.000041 s, × 1.2971
  mercurial       x000_revs_x000_added_x_copies         81f8ff2a9bf2 <https://phab.mercurial-scm.org/rHG81f8ff2a9bf20606fc89bc787983f592183e25b5> dd3267698d84 <https://phab.mercurial-scm.org/rHGdd3267698d84458686b3c5682ce027438900ffbd> :   0.005052 s,   0.006494 s,  +0.001442 s, × 1.2854
  pypy            x_revs_x_added_0_copies               aed021ee8ae8 099ed31b181b :   0.000219 s,   0.000339 s,  +0.000120 s, × 1.5479
  pypy            x_revs_x000_added_0_copies            4aa4e1f8e19a 359343b9ac0e :   0.000055 s,   0.000057 s,  +0.000002 s, × 1.0364
  pypy            x_revs_x_added_x_copies               ac52eb7bbbb0 72e022663155 :   0.000128 s,   0.000299 s,  +0.000171 s, × 2.3359
  pypy            x_revs_x00_added_x_copies             c3b14617fbd7 ace7255d9a26 :   0.001089 s,   0.001200 s,  +0.000111 s, × 1.1019
  pypy            x_revs_x000_added_x000_copies         df6f7a526b60 a83dc6a2d56f :   0.017407 s,   0.025120 s,  +0.007713 s, × 1.4431
  pypy            x000_revs_xx00_added_0_copies         89a76aede314 2f22446ff07e :   0.094175 s,   0.506921 s,  +0.412746 s, × 5.3828
  pypy            x000_revs_x000_added_x_copies         8a3b5bfd266e 2c68e87c3efe :   0.238009 s,   1.272060 s,  +1.034051 s, × 5.3446
  pypy            x000_revs_x000_added_x000_copies      89a76aede314 7b3dda341c84 :   0.125876 s,   0.690941 s,  +0.565065 s, × 5.4891
  pypy            x0000_revs_x_added_0_copies           d1defd0dc478 c9cb1334cc78 :   3.581556 s,  33.527067 s, +29.945511 s, × 9.3610
  pypy            x0000_revs_xx000_added_0_copies       bf2c629d0071 4ffed77c095c :   0.016721 s,   0.021970 s,  +0.005249 s, × 1.3139
  pypy            x0000_revs_xx000_added_x000_copies    08ea3258278e d9fa043f30c0 :   0.242367 s,   1.772094 s,  +1.529727 s, × 7.3116
  netbeans        x_revs_x_added_0_copies               fb0955ffcbcd a01e9239f9e7 :   0.000165 s,   0.000185 s,  +0.000020 s, × 1.1212
  netbeans        x_revs_x000_added_0_copies            6f360122949f 20eb231cc7d0 :   0.000114 s,   0.000135 s,  +0.000021 s, × 1.1842
  netbeans        x_revs_x_added_x_copies               1ada3faf6fb6 5a39d12eecf4 :   0.000296 s,   0.000329 s,  +0.000033 s, × 1.1115
  netbeans        x_revs_x00_added_x_copies             35be93ba1e2c 9eec5e90c05f :   0.001124 s,   0.001343 s,  +0.000219 s, × 1.1948
  netbeans        x000_revs_xx00_added_0_copies         eac3045b4fdd 51d4ae7f1290 :   0.013060 s,   0.029396 s,  +0.016336 s, × 2.2508
  netbeans        x000_revs_x000_added_x_copies         e2063d266acd 6081d72689dc :   0.017112 s,   0.040210 s,  +0.023098 s, × 2.3498
  netbeans        x000_revs_x000_added_x000_copies      ff453e9fee32 411350406ec2 :   0.660350 s,   4.556794 s,  +3.896444 s, × 6.9006
  netbeans        x0000_revs_xx000_added_x000_copies    588c2d1ced70 1aad62e59ddd :  10.032499 s, killed
  mozilla-central x_revs_x_added_0_copies               3697f962bb7b 7015fcdd43a2 :   0.000189 s,   0.000199 s,  +0.000010 s, × 1.0529
  mozilla-central x_revs_x000_added_0_copies            dd390860c6c9 40d0c5bed75d :   0.000462 s,   0.000639 s,  +0.000177 s, × 1.3831
  mozilla-central x_revs_x_added_x_copies               8d198483ae3b 14207ffc2b2f :   0.000270 s,   0.000542 s,  +0.000272 s, × 2.0074
  mozilla-central x_revs_x00_added_x_copies             98cbc58cc6bc 446a150332c3 :   0.001474 s,   0.001685 s,  +0.000211 s, × 1.1431
  mozilla-central x_revs_x000_added_x000_copies         3c684b4b8f68 0a5e72d1b479 :   0.004806 s,   0.006954 s,  +0.002148 s, × 1.4469
  mozilla-central x_revs_x0000_added_x0000_copies       effb563bb7e5 c07a39dc4e80 :   0.085150 s,   0.132938 s,  +0.047788 s, × 1.5612
  mozilla-central x000_revs_xx00_added_0_copies         6100d773079a 04a55431795e :   0.007064 s,   0.008683 s,  +0.001619 s, × 1.2292
  mozilla-central x000_revs_x000_added_x_copies         9f17a6fc04f9 2d37b966abed :   0.004741 s,   0.005956 s,  +0.001215 s, × 1.2563
  mozilla-central x000_revs_x000_added_x000_copies      7c97034feb78 4407bd0c6330 :   0.190133 s,   0.963905 s,  +0.773772 s, × 5.0696
  mozilla-central x0000_revs_xx000_added_0_copies       9eec5917337d 67118cc6dcad :   0.035651 s,   0.049239 s,  +0.013588 s, × 1.3811
  mozilla-central x0000_revs_xx000_added_x000_copies    f78c615a656c 96a38b690156 :   0.440694 s,   4.217003 s,  +3.776309 s, × 9.5690
  mozilla-central x00000_revs_x0000_added_x0000_copies  6832ae71433c 4c222a1d9a00 :  18.454163 s, killed
  mozilla-central x00000_revs_x00000_added_x000_copies  76caed42cf7c 1daa622bbe42 :  31.562719 s, killed
  mozilla-try     x_revs_x_added_0_copies               aaf6dde0deb8 9790f499805a :   0.001189 s,   0.001197 s,  +0.000008 s, × 1.0067
  mozilla-try     x_revs_x000_added_0_copies            d8d0222927b4 5bb8ce8c7450 :   0.001204 s,   0.001213 s,  +0.000009 s, × 1.0075
  mozilla-try     x_revs_x_added_x_copies               092fcca11bdb 936255a0384a :   0.000586 s,   0.000762 s,  +0.000176 s, × 1.3003
  mozilla-try     x_revs_x00_added_x_copies             b53d2fadbdb5 017afae788ec :   0.001845 s,   0.001909 s,  +0.000064 s, × 1.0347
  mozilla-try     x_revs_x000_added_x000_copies         20408ad61ce5 6f0ee96e21ad :   0.063822 s,   0.093021 s,  +0.029199 s, × 1.4575
  mozilla-try     x_revs_x0000_added_x0000_copies       effb563bb7e5 c07a39dc4e80 :   0.088038 s,   0.134536 s,  +0.046498 s, × 1.5282
  mozilla-try     x000_revs_xx00_added_0_copies         6100d773079a 04a55431795e :   0.007389 s,   0.009071 s,  +0.001682 s, × 1.2276
  mozilla-try     x000_revs_x000_added_x_copies         9f17a6fc04f9 2d37b966abed :   0.004868 s,   0.006206 s,  +0.001338 s, × 1.2749
  mozilla-try     x000_revs_x000_added_x000_copies      1346fd0130e4 4c65cbdabc1f :   0.222450 s,   1.150502 s,  +0.928052 s, × 5.1720
  mozilla-try     x0000_revs_x_added_0_copies           63519bfd42ee a36a2a865d92 :   0.370675 s,   1.114864 s,  +0.744189 s, × 3.0077
  mozilla-try     x0000_revs_x_added_x_copies           9fe69ff0762d bcabf2a78927 :   0.358020 s,   1.042658 s,  +0.684638 s, × 2.9123
  mozilla-try     x0000_revs_xx000_added_x_copies       156f6e2674f2 4d0f2c178e66 :   0.145235 s,   0.447402 s,  +0.302167 s, × 3.0805
  mozilla-try     x0000_revs_xx000_added_0_copies       9eec5917337d 67118cc6dcad :   0.037606 s,   0.051132 s,  +0.013526 s, × 1.3597
  mozilla-try     x0000_revs_xx000_added_x000_copies    89294cd501d9 7ccb2fc7ccb5 :   7.382439 s,  83.508590 s, +76.126151 s, × 11.3118
  mozilla-try     x0000_revs_x0000_added_x0000_copies   e928c65095ed e951f4ad123a :   7.273506 s,  55.079813 s, +47.806307 s, × 7.5727
  mozilla-try     x00000_revs_x00000_added_0_copies     dc8a3ca7010e d16fde900c9c :   1.074593 s,   1.442793 s,  +0.368200 s, × 1.3426
  mozilla-try     x00000_revs_x0000_added_x0000_copies  8d3fafa80d4b eb884023b810 :  27.746195 s, killed

REPOSITORY
  rHG Mercurial

BRANCH
  default

REVISION DETAIL
  https://phab.mercurial-scm.org/D9300

AFFECTED FILES
  rust/Cargo.lock
  rust/hg-core/Cargo.toml
  rust/hg-core/src/copy_tracing.rs

CHANGE DETAILS




To: marmoute, #hg-reviewers
Cc: mercurial-patches, mercurial-devel

Patch

diff --git a/rust/hg-core/src/copy_tracing.rs b/rust/hg-core/src/copy_tracing.rs
--- a/rust/hg-core/src/copy_tracing.rs
+++ b/rust/hg-core/src/copy_tracing.rs
@@ -1,6 +1,8 @@ 
 use crate::utils::hg_path::HgPathBuf;
 use crate::Revision;
 
+use im_rc::ordmap::OrdMap;
+
 use std::collections::HashMap;
 use std::collections::HashSet;
 
@@ -14,7 +16,7 @@ 
     path: Option<HgPathBuf>,
 }
 
-type TimeStampedPathCopies = HashMap<HgPathBuf, TimeStampedPathCopy>;
+type TimeStampedPathCopies = OrdMap<HgPathBuf, TimeStampedPathCopy>;
 
 /// hold parent 1, parent 2 and relevant files actions.
 pub type RevInfo = (Revision, Revision, ChangedFiles);
diff --git a/rust/hg-core/Cargo.toml b/rust/hg-core/Cargo.toml
--- a/rust/hg-core/Cargo.toml
+++ b/rust/hg-core/Cargo.toml
@@ -11,6 +11,7 @@ 
 [dependencies]
 byteorder = "1.3.4"
 hex = "0.4.2"
+im-rc = "15.0.*"
 lazy_static = "1.4.0"
 memchr = "2.3.3"
 rand = "0.7.3"
diff --git a/rust/Cargo.lock b/rust/Cargo.lock
--- a/rust/Cargo.lock
+++ b/rust/Cargo.lock
@@ -42,6 +42,14 @@ 
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "bitmaps"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "typenum 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "byteorder"
 version = "1.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -248,6 +256,7 @@ 
  "crossbeam 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "flate2 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "im-rc 15.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -286,6 +295,19 @@ 
 ]
 
 [[package]]
+name = "im-rc"
+version = "15.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitmaps 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_xoshiro 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sized-chunks 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "typenum 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "itertools"
 version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -558,6 +580,14 @@ 
 ]
 
 [[package]]
+name = "rand_xoshiro"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "rayon"
 version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -659,6 +689,15 @@ 
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "sized-chunks"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitmaps 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "typenum 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "strsim"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -729,6 +768,11 @@ 
 ]
 
 [[package]]
+name = "typenum"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "unicode-width"
 version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -749,6 +793,11 @@ 
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "version_check"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -820,6 +869,7 @@ 
 "checksum atty 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)" = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
 "checksum autocfg 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
+"checksum bitmaps 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "031043d04099746d8db04daf1fa424b2bc8bd69d92b25962dcde24da39ab64a2"
 "checksum byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
 "checksum cc 1.0.60 (registry+https://github.com/rust-lang/crates.io-index)" = "ef611cc68ff783f18535d77ddd080185275713d852c4f5cbb6122c462a7a825c"
 "checksum cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
@@ -844,6 +894,7 @@ 
 "checksum hermit-abi 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)" = "4c30f6d0bc6b00693347368a67d41b58f2fb851215ff1da49e90fe2c5c667151"
 "checksum hex 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "644f9158b2f133fd50f5fb3242878846d9eb792e445c893805ff0e3824006e35"
 "checksum humantime 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "df004cfca50ef23c36850aaaa59ad52cc70d0e90243c3c7737a4dd32dc7a3c4f"
+"checksum im-rc 15.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3ca8957e71f04a205cb162508f9326aea04676c8dfd0711220190d6b83664f3f"
 "checksum itertools 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "284f18f85651fe11e8a991b2adb42cb078325c996ed026d994719efcfca1d54b"
 "checksum jobserver 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)" = "5c71313ebb9439f74b00d9d2dcec36440beaf57a6aa0623068441dd7cd81a7f2"
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
@@ -878,6 +929,7 @@ 
 "checksum rand_distr 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "96977acbdd3a6576fb1d27391900035bf3863d4a16422973a409b488cf29ffb2"
 "checksum rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ca3129af7b92a17112d59ad498c6f81eaf463253766b90396d39ea7a39d6613c"
 "checksum rand_pcg 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "16abd0c1b639e9eb4d7c50c0b8100b0d0f849be2349829c740fe8e6eb4816429"
+"checksum rand_xoshiro 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a9fcdd2e881d02f1d9390ae47ad8e5696a9e4be7b547a1da2afbc61973217004"
 "checksum rayon 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "cfd016f0c045ad38b5251be2c9c0ab806917f82da4d36b2a327e5166adad9270"
 "checksum rayon-core 1.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "e8c4fec834fb6e6d2dd5eece3c7b432a52f0ba887cf40e595190c4107edc08bf"
 "checksum rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "678054eb77286b51581ba43620cc911abf02758c91f93f479767aed0f90458b2"
@@ -889,6 +941,7 @@ 
 "checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
 "checksum same-file 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "93fc1dc3aaa9bfed95e02e6eadabb4baf7e3078b0bd1b4d7b6b0b68378900502"
 "checksum scopeguard 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
+"checksum sized-chunks 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1ec31ceca5644fa6d444cc77548b88b67f46db6f7c71683b0f9336e671830d2f"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 "checksum syn 1.0.41 (registry+https://github.com/rust-lang/crates.io-index)" = "6690e3e9f692504b941dc6c3b188fd28df054f7fb8469ab40680df52fdcc842b"
 "checksum tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e24d9338a0a5be79593e2fa15a648add6138caa803e2d5bc782c371732ca9"
@@ -897,10 +950,12 @@ 
 "checksum thread_local 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
 "checksum time 0.1.44 (registry+https://github.com/rust-lang/crates.io-index)" = "6db9e6914ab8b1ae1c260a4ae7a49b6c5611b40328a735b21862567685e73255"
 "checksum twox-hash 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3bfd5b7557925ce778ff9b9ef90e3ade34c524b5ff10e239c69a42d546d2af56"
+"checksum typenum 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)" = "373c8a200f9e67a0c95e62a4f52fbf80c23b4381c05a17845531982fa99e6b33"
 "checksum unicode-width 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "9337591893a19b88d8d87f2cec1e73fad5cdfd10e5a6f349f498ad6ea2ffb1e3"
 "checksum unicode-xid 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f7fe0bb3479651439c9112f72b6c505038574c9fbb575ed1bf3b797fa39dd564"
 "checksum vcpkg 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)" = "6454029bf181f092ad1b853286f23e2c507d8e8194d01d92da4a55c274a5508c"
 "checksum vec_map 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f1bddf1187be692e79c5ffeab891132dfb0f236ed36a43c7ed39f1165ee20191"
+"checksum version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "078775d0255232fb988e6fccf26ddc9d1ac274299aaedcedce21c6f72cc533ce"
 "checksum wasi 0.10.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)" = "1a143597ca7c7793eff794def352d41792a93c481eb1042423ff7ff72ba2c31f"
 "checksum wasi 0.9.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)" = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
 "checksum winapi 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)" = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"