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


 use Coro::Storable;


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).


$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.


 Marc Lehmann <>