From: Peter Rabbitson <ribasushi@cpan.org>
Date: Tue, 9 Apr 2013 07:45:25 +0000 (+0200)
Subject: Tweak timing of t/zzzzzzz_perl_perf_bug.t - we started getting false positives
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=db2e53927f8913cdb8f3c2ec42820d99f53b1eb3;p=dbsrgits%2FDBIx-Class-Historic.git

Tweak timing of t/zzzzzzz_perl_perf_bug.t - we started getting false positives

http://www.cpantesters.org/cpan/report/356dd340-9de0-11e2-9265-e31b922ed931
http://www.cpantesters.org/cpan/report/2e2063f1-6bf4-1014-817e-b9974151da38

Not considering dropping the test because... well it is a good test ;)
---

diff --git a/t/zzzzzzz_perl_perf_bug.t b/t/zzzzzzz_perl_perf_bug.t
index f67c854..c1e0ab8 100644
--- a/t/zzzzzzz_perl_perf_bug.t
+++ b/t/zzzzzzz_perl_perf_bug.t
@@ -13,9 +13,11 @@ BEGIN {
     if DBICTest::RunMode->is_smoker;
 }
 
-use Benchmark;
+# globalllock so that the test runs alone
 use DBICTest ':GlobalLock';
 
+use Benchmark;
+
 # This is a rather unusual test.
 # It does not test any aspect of DBIx::Class, but instead tests the
 # perl installation this is being run under to see if it is:-
@@ -30,18 +32,18 @@ use DBICTest ':GlobalLock';
 # Perl Performance Issues on Red Hat Systems in
 # L<DBIx::Class::Manual::Troubleshooting>
 
-plan tests => 3;
-
-ok( 1, 'Dummy - prevents next test timing out' );
-
 # we do a benchmark test filling an array with blessed/overloaded references,
 # against an array filled with array refs.
 # On a sane system the ratio between these operation sets is 1 - 1.5,
 # whereas a bugged system gives a ratio of around 8
-# we therefore consider there to be a problem if the ratio is >= 2
+# we therefore consider there to be a problem if the ratio is >= $fail_ratio
+my $fail_ratio = 3;
+
+ok( $fail_ratio, "Testing for a blessed overload slowdown >= ${fail_ratio}x" );
+
 
 my $results = timethese(
-    -1,    # run for 1 CPU second each
+    -1,    # run for 1 WALL second each
     {
         no_bless => sub {
             my %h;
@@ -61,7 +63,7 @@ my $results = timethese(
 
 my $ratio = $results->{no_bless}->iters / $results->{bless_overload}->iters;
 
-ok( ( $ratio < 2 ), 'Overload/bless performance acceptable' )
+cmp_ok( $ratio, '<', $fail_ratio, 'Overload/bless performance acceptable' )
   || diag(
     "\n",
     "This perl has a substantial slow down when handling large numbers\n",
@@ -80,7 +82,7 @@ ok( ( $ratio < 2 ), 'Overload/bless performance acceptable' )
 
 SKIP: {
     skip "Not checking for bless handling as performance is OK", 1
-      if ( $ratio < 2 );
+      if Test::Builder->new->is_passing;
 
     {
         package    # don't want this in PAUSE
@@ -121,3 +123,5 @@ SKIP: {
         "file " . __FILE__ . "\n",
       );
 }
+
+done_testing;