Methods, system and computer program product are provided to improve the
efficiency of data transfers in a PPRC environment. A block of data to be
transferred is divided into tracks. Each track is allocated to a data
mover task control block (TCB) with a master TCB being assigned to
supervise the data mover TCBs. The tracks are then transferred from the
primary storage controller to the secondary controller in a piped fashion
over a link coupling the primary and secondary storage controllers.
However, the usage of resources is monitored by a resource management
algorithm and, if too many TCBs are being used for a transfer or if the
supply of data mover TCBs is exhausted, the transfer is automatically
switched to a serial, non-piped transfer with the master TCB serving as
the data mover TCB for the remaining tracks. In addition, the various
links coupling the primary and secondary storage controllers is monitored
to determine which link will provide the fastest transfer. If, during a
transfer of tracks over one link, a faster link is identified, the
transfer may be switched to the second, faster link.