X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=t%2F99rh_perl_perf_bug.t;h=8bed2d7e5d79642b10cf2bd255ce4714b5b6668e;hb=d3fba9e774c5c99eed84a182beab1ac25c68509a;hp=f481875d2f20773e3c4011da782942c7dcf6b00d;hpb=ec63d168501c9591c9af8888e916abbf5ccac77f;p=dbsrgits%2FDBIx-Class.git diff --git a/t/99rh_perl_perf_bug.t b/t/99rh_perl_perf_bug.t index f481875..8bed2d7 100644 --- a/t/99rh_perl_perf_bug.t +++ b/t/99rh_perl_perf_bug.t @@ -22,64 +22,100 @@ plan skip_all => 'Skipping RH perl performance bug tests as DBIC_NO_WARN_BAD_PERL set' if ( $ENV{DBIC_NO_WARN_BAD_PERL} ); -eval "use Benchmark"; +plan skip_all => 'Skipping as AUTOMATED_TESTING is set' + if ( $ENV{AUTOMATED_TESTING} ); + +eval "use Benchmark ':all'"; plan skip_all => 'needs Benchmark for testing' if $@; -plan tests => 2; +plan tests => 3; -{ - package # don't want this in PAUSE - TestRHBug; - use overload bool => sub { 0 } -} +ok( 1, 'Dummy - prevents next test timing out' ); -sub _has_bug_34925 { - my %thing; - my $r1 = \%thing; - my $r2 = \%thing; - bless $r1 => 'TestRHBug'; - return !!$r2; -} - -sub _possibly_has_bad_overload_performance { - return $] < 5.008009 && !_has_bug_34925(); -} - -# If the test here fails, you are running a 5.88 or older perl which -# has been patched to correct for an issue with bless/overload, but -# which *might* be susceptable to a severe performance issue caused -# by a partial fix. The performance issue is tested for in the second -# test. -# If *this* test fails, but the other test is OK, then you have a fixed -# perl and no need to worry. -ok( !_possibly_has_bad_overload_performance(), - 'Checking not susceptable to bless/overload performance problem' ); +# 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 my $results = timethese( -1, # run for 1 CPU second each { - overload => sub { - use overload q(<) => sub { }; + no_bless => sub { my %h; - for ( my $i = 0 ; $i < 5000 ; $i++ ) { - $h{$i} = bless [] => 'main'; + for ( my $i = 0 ; $i < 10000 ; $i++ ) { + $h{$i} = []; } }, - nooverload => sub { + bless_overload => sub { + use overload q(<) => sub { }; my %h; - for ( my $i = 0 ; $i < 5000 ; $i++ ) { + for ( my $i = 0 ; $i < 10000 ; $i++ ) { $h{$i} = bless [] => 'main'; } - } - } + }, + }, ); -# we are OK if there is less than a factor of 2 difference here -ok( ( ( $results->{nooverload}->iters / $results->{overload}->iters ) < 2 ), - 'Overload/bless performance acceptable' ) -# if the test above failed, look at the section titled -# Perl Performance Issues on Red Hat Systems in -# L -# Basically you may suffer severe performance issues when running -# DBIx::Class (and many other) modules. Look at getting a fixed -# version of the perl interpreter for your system. +my $ratio = $results->{no_bless}->iters / $results->{bless_overload}->iters; + +ok( ( $ratio < 2 ), 'Overload/bless performance acceptable' ) + || diag( + "\n", + "This perl has a substantial slow down when handling large numbers\n", + "of blessed/overloaded objects. This can severely adversely affect\n", + "the performance of DBIx::Class programs. Please read the section\n", + "in the Troubleshooting POD documentation entitled\n", + "'Perl Performance Issues on Red Hat Systems'\n", + "As this is an extremely serious condition, the only way to skip\n", + "over this test is to --force the installation, or to edit the test\n", + "file " . __FILE__ . "\n", + ); + +# We will only check for the difference in bless handling (whether the +# bless applies to the reference or the referent) if we have seen a +# performance issue... + +SKIP: { + skip "Not checking for bless handling as performance is OK", 1 + if ( $ratio < 2 ); + + { + package # don't want this in PAUSE + TestRHBug; + use overload bool => sub { 0 } + } + + sub _has_bug_34925 { + my %thing; + my $r1 = \%thing; + my $r2 = \%thing; + bless $r1 => 'TestRHBug'; + return !!$r2; + } + + sub _possibly_has_bad_overload_performance { + return $] < 5.008009 && !_has_bug_34925(); + } + + # If this next one fails then you almost certainly have a RH derived + # perl with the performance bug + # if this test fails, look at the section titled + # "Perl Performance Issues on Red Hat Systems" in + # L + # Basically you may suffer severe performance issues when running + # DBIx::Class (and many other) modules. Look at getting a fixed + # version of the perl interpreter for your system. + # + ok( !_possibly_has_bad_overload_performance(), + 'Checking whether bless applies to reference not object' ) + || diag( + "\n", + "This perl is probably derived from a buggy Red Hat perl build\n", + "Please read the section in the Troubleshooting POD documentation\n", + "entitled 'Perl Performance Issues on Red Hat Systems'\n", + "As this is an extremely serious condition, the only way to skip\n", + "over this test is to --force the installation, or to edit the test\n", + "file " . __FILE__ . "\n", + ); +}