---
name: "KiokuDB::LiveObjects"
section: "3pm"
platform: "linux"
package: "libkiokudb-perl"
version: "0.57-3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/KiokuDB::LiveObjects"
---

# KiokuDB::LiveObjects(3pm)

Live object set tracking

## 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.