delta-find: fix the computation of the `prev` value
authorPierre-Yves David <pierre-yves.david@octobus.net>
Thu, 23 Nov 2023 21:45:45 +0100
changeset 51332 2e169a222e63
parent 51331 7455cae67260
child 51333 0d92d62ecde0
delta-find: fix the computation of the `prev` value The previous computation was "wrong" it always used the tiprev, even when computing a delta in a non-append case (mostly benchmark). This never produced wrong delta on disk, but would misled debug or performance command. Since it does not have any actual user impact, I did not put this on stable. With the code fixed we can now use revisions in some search and it makes the test display more interesting behavior since the algorithm has more to work with.
mercurial/revlogutils/deltas.py
tests/test-sparse-revlog.t
--- a/mercurial/revlogutils/deltas.py	Fri Dec 22 01:33:40 2023 +0100
+++ b/mercurial/revlogutils/deltas.py	Thu Nov 23 21:45:45 2023 +0100
@@ -863,8 +863,7 @@
         assert self.revlog.delta_config.general_delta
         # also see issue6056
         sparse = self.revlog.delta_config.sparse_revlog
-        curr = len(self.revlog)
-        prev = curr - 1
+        prev = self.target_rev - 1
         deltachain = lambda rev: self.revlog._deltachain(rev)[0]
 
         # exclude already lazy tested base if any
--- a/tests/test-sparse-revlog.t	Fri Dec 22 01:33:40 2023 +0100
+++ b/tests/test-sparse-revlog.t	Thu Nov 23 21:45:45 2023 +0100
@@ -164,7 +164,21 @@
      4971    4970      -1       3        5     4930    snap
   $ hg debug-delta-find SPARSE-REVLOG-TEST-FILE 4971
   DBG-DELTAS-SEARCH: SEARCH rev=4971
-  DBG-DELTAS-SEARCH: ROUND #1 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #1 - 3 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4329
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=13781
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=173765
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=106516 (BAD)
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4335
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=14385
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=171587
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=105187 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4962
   DBG-DELTAS-SEARCH:     type=snapshot-4
   DBG-DELTAS-SEARCH:     size=18296
@@ -172,7 +186,14 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=30377
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=16872 (BAD)
-  DBG-DELTAS-SEARCH: ROUND #2 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #2 - 2 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4325
+  DBG-DELTAS-SEARCH:     type=snapshot-3
+  DBG-DELTAS-SEARCH:     size=17384
+  DBG-DELTAS-SEARCH:     base=4318
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=178121
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=109064 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4930
   DBG-DELTAS-SEARCH:     type=snapshot-3
   DBG-DELTAS-SEARCH:     size=39228
@@ -189,7 +210,7 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=82661
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=49132 (BAD)
-  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=3 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
+  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=6 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
 
   $ cat << EOF >>.hg/hgrc
   > [storage]
@@ -198,10 +219,24 @@
   > EOF
 
   $ hg debug-delta-find SPARSE-REVLOG-TEST-FILE 4971 --quiet
-  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=3 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
+  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=6 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
   $ hg debug-delta-find SPARSE-REVLOG-TEST-FILE 4971 --source full
   DBG-DELTAS-SEARCH: SEARCH rev=4971
-  DBG-DELTAS-SEARCH: ROUND #1 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #1 - 3 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4329
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=13781
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=173765
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=106516 (BAD)
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4335
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=14385
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=171587
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=105187 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4962
   DBG-DELTAS-SEARCH:     type=snapshot-4
   DBG-DELTAS-SEARCH:     size=18296
@@ -209,7 +244,14 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=30377
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=16872 (BAD)
-  DBG-DELTAS-SEARCH: ROUND #2 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #2 - 2 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4325
+  DBG-DELTAS-SEARCH:     type=snapshot-3
+  DBG-DELTAS-SEARCH:     size=17384
+  DBG-DELTAS-SEARCH:     base=4318
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=178121
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=109064 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4930
   DBG-DELTAS-SEARCH:     type=snapshot-3
   DBG-DELTAS-SEARCH:     size=39228
@@ -226,7 +268,7 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=82661
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=49132 (BAD)
-  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=3 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
+  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=6 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
   $ hg debug-delta-find SPARSE-REVLOG-TEST-FILE 4971 --source storage
   DBG-DELTAS-SEARCH: SEARCH rev=4971
   DBG-DELTAS-SEARCH: ROUND #1 - 1 candidates - cached-delta
@@ -240,7 +282,21 @@
   DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=1 - search-rounds=1 try-count=1 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
   $ hg debug-delta-find SPARSE-REVLOG-TEST-FILE 4971 --source p1
   DBG-DELTAS-SEARCH: SEARCH rev=4971
-  DBG-DELTAS-SEARCH: ROUND #1 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #1 - 3 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4329
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=13781
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=173765
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=106516 (BAD)
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4335
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=14385
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=171587
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=105187 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4962
   DBG-DELTAS-SEARCH:     type=snapshot-4
   DBG-DELTAS-SEARCH:     size=18296
@@ -248,7 +304,14 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=30377
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=16872 (BAD)
-  DBG-DELTAS-SEARCH: ROUND #2 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #2 - 2 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4325
+  DBG-DELTAS-SEARCH:     type=snapshot-3
+  DBG-DELTAS-SEARCH:     size=17384
+  DBG-DELTAS-SEARCH:     base=4318
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=178121
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=109064 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4930
   DBG-DELTAS-SEARCH:     type=snapshot-3
   DBG-DELTAS-SEARCH:     size=39228
@@ -265,10 +328,24 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=82661
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=49132 (BAD)
-  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=3 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
+  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=6 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
   $ hg debug-delta-find SPARSE-REVLOG-TEST-FILE 4971 --source p2
   DBG-DELTAS-SEARCH: SEARCH rev=4971
-  DBG-DELTAS-SEARCH: ROUND #1 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #1 - 3 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4329
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=13781
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=173765
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=106516 (BAD)
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4335
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=14385
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=171587
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=105187 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4962
   DBG-DELTAS-SEARCH:     type=snapshot-4
   DBG-DELTAS-SEARCH:     size=18296
@@ -276,7 +353,14 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=30377
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=16872 (BAD)
-  DBG-DELTAS-SEARCH: ROUND #2 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #2 - 2 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4325
+  DBG-DELTAS-SEARCH:     type=snapshot-3
+  DBG-DELTAS-SEARCH:     size=17384
+  DBG-DELTAS-SEARCH:     base=4318
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=178121
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=109064 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4930
   DBG-DELTAS-SEARCH:     type=snapshot-3
   DBG-DELTAS-SEARCH:     size=39228
@@ -293,10 +377,24 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=82661
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=49132 (BAD)
-  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=3 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
+  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=6 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
   $ hg debug-delta-find SPARSE-REVLOG-TEST-FILE 4971 --source prev
   DBG-DELTAS-SEARCH: SEARCH rev=4971
-  DBG-DELTAS-SEARCH: ROUND #1 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #1 - 3 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4329
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=13781
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=173765
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=106516 (BAD)
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4335
+  DBG-DELTAS-SEARCH:     type=snapshot-4
+  DBG-DELTAS-SEARCH:     size=14385
+  DBG-DELTAS-SEARCH:     base=4325
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=171587
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=105187 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4962
   DBG-DELTAS-SEARCH:     type=snapshot-4
   DBG-DELTAS-SEARCH:     size=18296
@@ -304,7 +402,14 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=30377
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=16872 (BAD)
-  DBG-DELTAS-SEARCH: ROUND #2 - 1 candidates - search-down
+  DBG-DELTAS-SEARCH: ROUND #2 - 2 candidates - search-down
+  DBG-DELTAS-SEARCH:   CANDIDATE: rev=4325
+  DBG-DELTAS-SEARCH:     type=snapshot-3
+  DBG-DELTAS-SEARCH:     size=17384
+  DBG-DELTAS-SEARCH:     base=4318
+  DBG-DELTAS-SEARCH:     uncompressed-delta-size=178121
+  DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
+  DBG-DELTAS-SEARCH:     DELTA: length=109064 (BAD)
   DBG-DELTAS-SEARCH:   CANDIDATE: rev=4930
   DBG-DELTAS-SEARCH:     type=snapshot-3
   DBG-DELTAS-SEARCH:     size=39228
@@ -321,6 +426,6 @@
   DBG-DELTAS-SEARCH:     uncompressed-delta-size=82661
   DBG-DELTAS-SEARCH:     delta-search-time=* (glob)
   DBG-DELTAS-SEARCH:     DELTA: length=49132 (BAD)
-  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=3 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
+  DBG-DELTAS: FILELOG:SPARSE-REVLOG-TEST-FILE: rev=4971: delta-base=4930 is-cached=0 - search-rounds=3 try-count=6 - delta-type=snapshot snap-depth=4 - p1-chain-length=15 p2-chain-length=-1 - duration=* (glob)
 
   $ cd ..