fi_sockets(7) Libfabric Programmer's Manual
The Sockets Fabric Provider
The sockets provider is a general purpose provider that can be used on any system that supports TCP sockets. The provider is not intended to provide performance improvements over regular TCP sockets, but rather to allow developers to write, test, and debug application code even on platforms that do not have high-performance fabric hardware. The sockets provider supports all libfabric provider requirements and interfaces.
The sockets provider supports all the features defined for the libfabric API. Key features include:
- Endpoint types
- The provider supports all endpoint types: FI_EP_MSG, FI_EP_RDM, and FI_EP_DGRAM.
- Endpoint capabilities
- The following data transfer interface is supported for a all endpoint types: fi_msg. Additionally, these interfaces are supported for reliable endpoints (FI_EP_MSG and FI_EP_RDM): fi_tagged, fi_atomic, and fi_rma.
- The sockets provider supports all operational modes including FI_CONTEXT and FI_MSG_PREFIX.
- Sockets provider supports both FI_PROGRESS_AUTO and FI_PROGRESS_MANUAL, with a default set to auto. When progress is set to auto, a background thread runs to ensure that progress is made for asynchronous requests.
Sockets provider attempts to emulate the entire API set, including all defined options. In order to support development on a wide range of systems, it is implemented over TCP sockets. As a result, the performance numbers are lower compared to other providers implemented over high-speed fabric, and lower than what an application might see implementing to sockets directly.