From: Peter Rabbitson Date: Sun, 26 Sep 2010 17:36:41 +0000 (+0200) Subject: Fix compose_namespace rsrc leaks, introduce a badass leaktracer X-Git-Tag: v0.08124~63 X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=dbsrgits%2FDBIx-Class.git;a=commitdiff_plain;h=a8c2c746a5bb98671cbe3a58f26cd115b7770cf9 Fix compose_namespace rsrc leaks, introduce a badass leaktracer --- diff --git a/Changes b/Changes index b135616..b91006b 100644 --- a/Changes +++ b/Changes @@ -17,6 +17,7 @@ Revision history for DBIx::Class * Fixes - Fix memory leak during populate() on 5.8.x perls + - Fix result_soutrce_instance leaks on compose_namespace - Make sure exception_action does not allow exception-hiding due to badly-written handlers (the mechanism was never meant to be able to suppress exceptions) @@ -62,6 +63,8 @@ Revision history for DBIx::Class - DT-related tests now require a DateTime >= 0.55 (RT#60324) - Makefile.PL now provides a pre-parsed DBIC version to the Opt::Dep pod generator + - t/52leaks.t now performs very aggressive leak detection in + author/smoker mode 0.08123 2010-06-12 14:46 (UTC) * Fixes diff --git a/lib/DBIx/Class/Schema.pm b/lib/DBIx/Class/Schema.pm index 77a7fe7..3c992ab 100644 --- a/lib/DBIx/Class/Schema.pm +++ b/lib/DBIx/Class/Schema.pm @@ -898,6 +898,7 @@ sub compose_namespace { my $schema = $self->clone; { no warnings qw/redefine/; + no strict qw/refs/; # local *Class::C3::reinitialize = sub { }; foreach my $moniker ($schema->sources) { my $source = $schema->source($moniker); @@ -906,8 +907,14 @@ sub compose_namespace { $target_class => $source->result_class, ($base ? $base : ()) ); $source->result_class($target_class); - $target_class->result_source_instance($source) - if $target_class->can('result_source_instance'); + if ($target_class->can('result_source_instance')) { + + # since the newly created classes are registered only with + # the instance of $schema, it should be safe to weaken + # the ref (it will GC when $schema is destroyed) + $target_class->result_source_instance($source); + weaken ${"${target_class}::__cag_result_source_instance"}; + } $schema->register_source($moniker, $source); } } diff --git a/t/52leaks.t b/t/52leaks.t index 7ecec49..4625547 100644 --- a/t/52leaks.t +++ b/t/52leaks.t @@ -2,57 +2,170 @@ use strict; use warnings; use Test::More; +use Scalar::Util qw/refaddr reftype weaken/; +use Carp qw/longmess/; +use Try::Tiny; use lib qw(t/lib); +use DBICTest::RunMode; +my $have_test_cycle; BEGIN { require DBIx::Class::Optional::Dependencies; - plan skip_all => 'Test needs: ' . DBIx::Class::Optional::Dependencies->req_missing_for ('test_leaks') - unless ( DBIx::Class::Optional::Dependencies->req_ok_for ('test_leaks') ); + $have_test_cycle = DBIx::Class::Optional::Dependencies->req_ok_for ('test_leaks') + and import Test::Memory::Cycle; } -use DBICTest; -use DBICTest::Schema; -use Scalar::Util 'weaken'; -use namespace::clean; +# preload stuff so that we don't trap globals +use DBI; +use Errno; +use Class::Struct; +use DBD::SQLite; +use FileHandle; + +# this is what holds all weakened refs to be checked for leakage +my $weak_registry = {}; + +# Skip the heavy-duty leak tracing when just doing an install +unless (DBICTest::RunMode->is_plain) { + no warnings qw/redefine once/; + no strict qw/refs/; + + # override bless so that we can catch each and every object created + *CORE::GLOBAL::bless = sub { + my $obj = CORE::bless( + $_[0], (@_ > 1) ? $_[1] : do { + my ($class, $fn, $line) = caller(); + fail ("bless() of $_[0] into $class without explicit class specification at $fn line $line") + if $class =~ /^ (?: DBIx\:\:Class | DBICTest ) /x; + $class; + } + ); + + my $slot = (sprintf '%s=%s(0x%x)', # so we don't trigger stringification + ref $obj, + reftype $obj, + refaddr $obj, + ); + + # weaken immediately to avoid weird side effects + $weak_registry->{$slot} = { weakref => $obj, strace => longmess() }; + weaken $weak_registry->{$slot}{weakref}; + + return $obj; + }; + + for my $func (qw/try catch finally/) { + my $orig = \&{"Try::Tiny::$func"}; + *{"Try::Tiny::$func"} = sub (&;@) { + + my $slot = sprintf ('CODE(0x%x)', refaddr $_[0]); + + $weak_registry->{$slot} = { weakref => $_[0], strace => longmess() }; + weaken $weak_registry->{$slot}{weakref}; + + goto $orig; + } + } +} + +{ + require DBICTest; -import Test::Memory::Cycle; + my $schema = DBICTest->init_schema; + my $rs = $schema->resultset ('Artist'); + my $storage = $schema->storage; -my $weak; + ok ($storage->connected, 'we are connected'); -{ - my $s = $weak->{schema} = DBICTest->init_schema; - ok ($s->storage->connected, 'we are connected'); - memory_cycle_ok($s, 'No cycles in schema'); + my $row_obj = $rs->next; + ok ($row_obj, 'row from db'); + + my ($mc_row_obj, $pager, $pager_explicit_count) = $schema->txn_do (sub { + + my $artist = $rs->create ({ + name => 'foo artist', + cds => [{ + title => 'foo cd', + year => 1984, + }], + }); + + my $pg = $rs->search({}, { rows => 1})->page(2)->pager; + + my $pg_wcount = $rs->page(4)->pager->total_entries (66); + + return ($artist, $pg, $pg_wcount); + }); + + is ($pager->next_page, 3, 'There is one more page available'); + + # based on 66 per 10 pages + is ($pager_explicit_count->last_page, 7, 'Correct last page'); - my $storage = $weak->{storage} = $s->storage; - memory_cycle_ok($storage, 'No cycles in storage'); + my $base_collection = { + schema => $schema, + storage => $storage, - my $rs = $weak->{resultset} = $s->resultset ('Artist'); - memory_cycle_ok($rs, 'No cycles in resultset'); + resultset => $rs, + row_object => $row_obj, - my $rsrc = $weak->{resultsource} = $rs->result_source; - memory_cycle_ok($rsrc, 'No cycles in resultsource'); + result_source => $rs->result_source, - my $row = $weak->{row} = $rs->first; - memory_cycle_ok($row, 'No cycles in row'); + fresh_pager => $rs->page(5)->pager, + pager => $pager, + pager_explicit_count => $pager_explicit_count, - my $sqla = $weak->{sqla} = $s->storage->sql_maker; - memory_cycle_ok($sqla, 'No cycles in SQL maker'); + sql_maker => $storage->sql_maker, + dbh => $storage->_dbh + }; - my $dbh = $weak->{dbh} = $s->storage->_get_dbh; - memory_cycle_ok($dbh, 'No cycles in DBI handle'); + memory_cycle_ok ($base_collection, 'No cycles in the object collection') + if $have_test_cycle; - for (@{$dbh->{ChildHandles}}) { - $weak->{"$_"} = $_ if $_; + for (keys %$base_collection) { + $weak_registry->{"basic $_"} = { weakref => $base_collection->{$_} }; + weaken $weak_registry->{"basic $_"}{weakref}; } - weaken $_ for values %$weak; - memory_cycle_ok($weak, 'No cycles in weak object collection'); } -for (keys %$weak) { - ok (! $weak->{$_}, "No $_ leaks"); +memory_cycle_ok($weak_registry, 'No cycles in the weakened object collection') + if $have_test_cycle; + +# FIXME +# For reasons I can not yet fully understand the table() god-method (located in +# ::ResultSourceProxy::Table) attaches an actual source instance to each class +# as virtually *immortal* class-data. +# For now just blow away these instances manually but there got to be a saner way +$_->result_source_instance(undef) for ( + 'DBICTest::BaseResult', + map { DBICTest::Schema->class ($_) } DBICTest::Schema->sources +); + +# FIXME +# same problem goes for the schema - its classdata contains live result source +# objects, which to add insult to the injury are *different* instances from the +# ones we destroyed above +DBICTest::Schema->source_registrations(undef); + +my $tb = Test::More->builder; +for my $slot (keys %$weak_registry) { + # SQLT is a piece of shit, leaks all over + next if $slot =~ /^SQL\:\:Translator/; + + ok (! defined $weak_registry->{$slot}{weakref}, "No leaks of $slot") or do { + my $diag = ''; + + $diag .= Devel::FindRef::track ($weak_registry->{$slot}{weakref}, 20) . "\n" + if ( $ENV{TEST_VERBOSE} && try { require Devel::FindRef }); + + if (my $stack = $weak_registry->{$slot}{strace}) { + $diag .= " Reference first seen$stack"; + } + + diag $diag if $diag; + }; } done_testing;