Returns data from the persistent cache when given an array of cache IDs.
$cids: An array of cache IDs for the data to retrieve. This is passed by reference, and will have the IDs successfully returned from cache removed.
$bin: The cache bin where the data is stored.
An array of the items successfully returned from cache indexed by cid.
function cache_get_multiple(array &$cids, $bin = 'cache') {
return _cache_get_object($bin)
->getMultiple($cids);
}