cray_cassini

Network performance counter groups for the Cassini NIC

Author:: Hewlett Packard Enterprise Development LP.
Copyright:: Copyright 2021,2023-2024 Hewlett Packard Enterprise Development LP.
Manual section:: 5

DESCRIPTION

CrayPat supports experiments that make use of the network performance counters on the Cassini NIC. These counters are accessed through use of the environment variable PAT_RT_PERFCTR and related environment variables. Access to the performance counters on the Cassini NIC is provided by the PAPI cray_cassini component. Execute the command papi_component_avail to determine if this component is supported on your system.

All PAPI utilities such as papi_native_avail can access and list these events. However, when listed via papi_native_avail, the event names contain a cray_cassini::: prefix. This prefix is not required when specifying the event name to CrayPat via the environment variable PAT_RT_PERFCTR or related runtime environment variables.

To list the available events, execute the command papi_native_avail on a compute node and filter for the desired component. For example:

$ srun papi_native_avail -i cray_cassini

For complete lists of the hardware counter events currently supported organized by processor family, execute pat_help and select the counters topic.

By default, counter values for a given Cassini event are aggregated across all Cassini NIC devices attached to the executing process. To acquire the value for a given Cassini event for each NIC device attached to the executing process use the devx modifier when using the PAT_RT_PERFCTR environment variable. See the intro_craypat(1) man page for more details.

The Message-Passing Interface (MPI) library supports environment variables that allow access to the Cassini NIC performance counters, although it does not support the PAPI event naming conventions. See the intro_mpi(3) man page for details.

cray_cassini

Network performance counter groups for the Cassini NIC

DESCRIPTION

SEE ALSO