Bug #57840 MTR: parallel execution breaks with smart ordering of test cases

There were actually more problems in this area:
  Slaves (if any) were unconditionally restarted, this appears unnecessary.
  Sort criteria were suboptimal, included the test name.
Added logic to "reserve" a sequence of tests with same config for one thread
Got rid of sort_criteria hash, put it into the test case itself
Adds little sanity check that expected worker picks up test
Fixed some tests that may fail if starting on running server
Some of these fail only if *same* test is repeated.
Finally, special sorting of tests that do --force-restart

1 files changed, 13 insertions, 8 deletions

diff --git a/mysql-test/lib/mtr_cases.pm b/mysql-test/lib/mtr_cases.pm
index 7d25a72212a..7961fa6fa7d 100644
--- a/mysql-test/lib/mtr_cases.pm
+++ b/mysql-test/lib/mtr_cases.pm
@@ -170,8 +170,6 @@ sub collect_test_cases ($$$) {
   if ( $opt_reorder && !$quick_collect)
   {
     # Reorder the test cases in an order that will make them faster to run
-    my %sort_criteria;
-
     # Make a mapping of test name to a string that represents how that test
     # should be sorted among the other tests.  Put the most important criterion
     # first, then a sub-criterion, then sub-sub-criterion, etc.
@@ -183,24 +181,31 @@ sub collect_test_cases ($$$) {
       # Append the criteria for sorting, in order of importance.
       #
       push(@criteria, "ndb=" . ($tinfo->{'ndb_test'} ? "A" : "B"));
+      push(@criteria, $tinfo->{template_path});
       # Group test with equal options together.
       # Ending with "~" makes empty sort later than filled
       my $opts= $tinfo->{'master_opt'} ? $tinfo->{'master_opt'} : [];
       push(@criteria, join("!", sort @{$opts}) . "~");
+      # Add slave opts if any
+      if ($tinfo->{'slave_opt'})
+      {
+	push(@criteria, join("!", sort @{$tinfo->{'slave_opt'}}));
+      }
+      # This sorts tests with force-restart *before* identical tests
+      push(@criteria, $tinfo->{force_restart} ? "force-restart" : "no-restart");
 
-      $sort_criteria{$tinfo->{name}} = join(" ", @criteria);
+      $tinfo->{criteria}= join(" ", @criteria);
     }
 
-    @$cases = sort {
-      $sort_criteria{$a->{'name'}} . $a->{'name'} cmp
-	$sort_criteria{$b->{'name'}} . $b->{'name'}; } @$cases;
+    @$cases = sort {$a->{criteria} cmp $b->{criteria}; } @$cases;
 
     # For debugging the sort-order
     # foreach my $tinfo (@$cases)
     # {
-    #   print("$sort_criteria{$tinfo->{'name'}} -> \t$tinfo->{'name'}\n");
+    #   my $tname= $tinfo->{name} . ' ' . $tinfo->{combination};
+    #   my $crit= $tinfo->{criteria};
+    #   print("$tname\n\t$crit\n");
     # }
-
   }
 
   if (defined $print_testcases){