NAME

       KiokuDB::LiveObjects - Live object set tracking

VERSION

       version 0.57

SYNOPSIS

           $live_objects->insert( $entry => $object );

           $live_objects->insert( $id => $object );

           my $id = $live_objects->object_to_id( $object );

           my $obj = $live_objects->id_to_object( $id );

           my $scope = $live_objects->new_scope;

DESCRIPTION

       This object keeps track of the set of live objects, their associated IDs, and the storage
       entries.

ATTRIBUTES

       clear_leaks
           Boolean. Defaults to false.

           If true, when the last known scope is removed but some objects are still live they
           will be removed from the live object set.

           Note that this does NOT prevent leaks (memory cannot be reclaimed), it merely prevents
           stale objects from staying loaded.

       leak_tracker
           This is a coderef or object.

           If any objects are leaked (see "clear_leaks") then the this can be used to report
           them, or to break the circular structure.

           When an object is provided the "leaked_objects" method is called. The coderef is
           simply invoked with the objects as arguments.

           Triggered after "clear_leaks" causes "clear" to be called.

           For example, to break cycles you can use Data::Structure::Util's "circular_off"
           function:

               use Data::Structure::Util qw(circular_off);

               $dir->live_objects->leak_tracker(sub {
                   my @leaked_objects = @_;
                   circular_off($_) for @leaked_objects;
               });

       keep_entries
           EXPERIMENTAL

           When true (the default), KiokuDB::Entries loaded from the backend or created by the
           collapser are kept around.

           This results in a considerable memory overhead, so it's no longer required.

METHODS

       insert
           Takes pairs, id or entry as the key, and object as the value, registering the objects.

       objects_to_ids
       object_to_id
           Given objects, returns their IDs, or undef for objects which not registered.

       objects_to_entries
       object_to_entry
           Given objects, find the corresponding entries.

       ids_to_objects
       id_to_object
           Given IDs, find the corresponding objects.

       ids_to_entries
           Given IDs, find the corresponding entries.

       update_entries
           Given entries, replaces the live entries of the corresponding objects with the newly
           updated ones.

           The objects must already be in the live object set.

           This method is called on a successful transaction commit.

       new_scope
           Creates a new KiokuDB::LiveObjects::Scope, with the current scope as its parent.

       current_scope
           The current KiokuDB::LiveObjects::Scope instance.

           This is the scope into which newly registered objects are pushed.

       new_txn
           Creates a new KiokuDB::LiveObjects::TXNScope, with the current txn scope as its
           parent.

       txn_scope
           The current KiokuDB::LiveObjects::TXNScope.

       clear
           Forces a clear of the live object set.

           This removes all objects and entries, and can be useful in the case of leaks (to
           prevent false positives on lookups).

           Note that this does not actually break the circular structures, so the leak is
           unresolved, but the objects are no longer considered live by the KiokuDB instance.

       live_entries
       live_objects
       live_ids
           Enumerates the live entries, objects or ids.

       rollback_entries
           Called by "rollback" in KiokuDB::LiveObjects::TXNScope.

       remove
           Removes entries from the live object set.

       remove_scope $scope
           Removes a scope from the set of known scopes.

           Also calls "detach_scope", and calls "KiokuDB::LiveObjects::Scope/clear" on the scope
           itself.

       detach_scope $scope
           Detaches $scope if it's the current scope.

           This prevents "push" from being called on this scope object implicitly anymore.

AUTHOR

       Yuval Kogman <nothingmuch@woobling.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2014 by Yuval Kogman, Infinity Interactive.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.