Coro::Storable.3pm

Langue: en

Autres versions - même langue

Version: 2007-12-02 (mandriva - 01/05/08)

Section: 3 (Bibliothèques de fonctions)

NAME

Coro::Storable - offer a more fine-grained Storable interface

SYNOPSIS

  use Coro::Storable;
 
 

DESCRIPTION

This module implements a few functions from the Storable module in a way so that it cede's more often. Some applications (such as the Crossfire game server) sometimes need to load large Storable objects without blocking the server for a long time.

This is being implemented by using a perlio layer that feeds only small amounts of data (512 bytes per call) into Storable, and "Coro::cede"'ing regularly (at most 1000 times per second by default, though).

As it seems that Storable is not reentrant, this module also serialises calls to freeze and thaw between coroutines as necessary (for this to work reliably you always have to use this module, however).

FUNCTIONS

$ref = thaw $pst
Retrieve an object from the given $pst, which must have been created with "Coro::Storable::freeze" or "Storable::store_fd"/"Storable::store" (sorry, but Storable uses incompatible formats for disk/mem objects).

This works by calling "Coro::cede" for every 4096 bytes read in.

$pst = freeze $ref
Freeze the given scalar into a Storable object. It uses the same format as "Storable::store_fd".

This works by calling "Coro::cede" for every write that Storable issues. Unfortunately, Storable often makes many very small writes, so it is rather inefficient. But it does keep the latency low.

$pst = nfreeze $ref
Same as "freeze" but is compatible to "Storable::nstore_fd" (note the "n").
$pst = blocking_freeze $ref
Same as "freeze" but is guaranteed to block. This is useful e.g. in "Coro::Util::fork_eval" when you want to serialise a data structure for use with the "thaw" function for this module. You cannot use "Storable::freeze" for this as Storable uses incompatible formats for memory and file images.
$pst = blocking_nfreeze $ref
Same as "blocking_freeze" but uses "nfreeze" internally.
$guard = guard;
Acquire the Storable lock, for when you want to call Storable yourself.

AUTHOR

  Marc Lehmann <schmorp@schmorp.de>
  http://home.schmorp.de/