Escali 4.4 manual Support for other interconnects, MPI-2 Features, Zerocopy protocol

Section: 2.4 Support for other interconnects

2.3.5 Zerocopy protocol

The zerocopy protocol is special case of the transporter protocol t. It includes the same steps as a transporter except that data is written directly into the receivers buffer instead of being buffered in the transporter-ringbuffer.

The zerocopy protocol is selected if the underlying hardware can support it. To disable it, set the zerocopy_count or the zerocopy_size parameters to 0

2.4 Support for other interconnects

A uDAPL 1.1 module must be developed to interface other interconnects to Scali MPI Connect. The listing below identifies the particular functions that must be implemented in order for SMC to be able to use a uDAPL-implementation:

dat_cr_accept dat_cr_query dat_cr_reject dat_ep_connect dat_ep_create dat_ep_disconnect dat_ep_free dat_ep_post_rdma_write dat_evd_create dat_evd_dequeue dat_evd_free dat_evd_wait dat_ia_close dat_ia_open dat_ia_query dat_lmr_create dat_lmr_free dat_psp_create dat_psp_free dat_pz_create dat_pz_free dat_set_consumer_context

2.5 MPI-2 Features

At the time being SMC does not implement the full MPI-2 functionality. At the same time some users are asking for parts of the MPI-2 functionality, in particular the MPI-I/O functions. To fill the users needs Scali are now using the Open Source ROMIO software to offer this functionality.

Scali MPI Connect Release 4.4 Users Guide 18