gmx::GpuTaskAssignmentsBuilder Class Reference

#include <gromacs/taskassignment/taskassignment.h>

Description

Builder for the GpuTaskAssignments for all ranks on this node.

This will coordinate the final stages of task assignment and reporting, and build the GpuTaskAssignments object used to configure the modules that might run tasks on GPUs.

Communicates between ranks on a node to coordinate task assignment between them onto available hardware, e.g. accelerators.

Todo:

Later, this might become a loop over all registered modules relevant to the mdp inputs, to find those that have such tasks.

Todo:

Later we might need the concept of computeTasksOnThisRank, from which we construct gpuTasksOnThisRank.

Currently the DD code assigns duty to ranks that can include PP work that currently can be executed on a single GPU, if present and compatible. This has to be coordinated across PP ranks on a node, with possible multiple devices or sharing devices on a node, either from the user selection, or automatically.

Public Member Functions
	GpuTaskAssignmentsBuilder ()
	Constructor.
GpuTaskAssignments	build (const std::vector< int > &gpuIdsToUse, const std::vector< int > &userGpuTaskAssignment, const gmx_hw_info_t &hardwareInfo, const t_commrec *cr, const gmx_multisim_t *ms, const PhysicalNodeCommunicator &physicalNodeComm, TaskTarget nonbondedTarget, TaskTarget pmeTarget, TaskTarget bondedTarget, TaskTarget updateTarget, bool useGpuForNonbonded, bool useGpuForPme, bool rankHasPpTask, bool rankHasPmeTask)
	Builds a GpuTaskAssignments. More...

Member Function Documentation

GpuTaskAssignments gmx::GpuTaskAssignmentsBuilder::build	(	const std::vector< int > &	gpuIdsToUse,
		const std::vector< int > &	userGpuTaskAssignment,
		const gmx_hw_info_t &	hardwareInfo,
		const t_commrec *	cr,
		const gmx_multisim_t *	ms,
		const PhysicalNodeCommunicator &	physicalNodeComm,
		TaskTarget	nonbondedTarget,
		TaskTarget	pmeTarget,
		TaskTarget	bondedTarget,
		TaskTarget	updateTarget,
		bool	useGpuForNonbonded,
		bool	useGpuForPme,
		bool	rankHasPpTask,
		bool	rankHasPmeTask
	)

Builds a GpuTaskAssignments.

This method reconciles

• user mdrun command-line options,
• the results of hardware detection
• the duty assigned by the DD setup,
• the requested simulation modules, and
• the possible existence of multi-simulations

to assign the GPUs on each physical node to the tasks on the ranks of that node.

Parameters

[in]	gpuIdsToUse	The compatible GPUs that the user permitted us to use.
[in]	userGpuTaskAssignment	The user-specified assignment of GPU tasks to device IDs.
[in]	hardwareInfo	The detected hardware
[in]	cr	Communication object.
[in]	ms	Multi-simulation handler.
[in]	physicalNodeComm	Communication object for this physical node.
[in]	nonbondedTarget	The user's choice for mdrun -nb for where to assign short-ranged nonbonded interaction tasks.
[in]	pmeTarget	The user's choice for mdrun -pme for where to assign long-ranged PME nonbonded interaction tasks.
[in]	bondedTarget	The user's choice for mdrun -bonded for where to assign tasks.
[in]	updateTarget	The user's choice for mdrun -update for where to assign tasks.
[in]	useGpuForNonbonded	Whether GPUs will be used for nonbonded interactions.
[in]	useGpuForPme	Whether GPUs will be used for PME interactions.
[in]	rankHasPpTask	Whether this rank has a PP task
[in]	rankHasPmeTask	Whether this rank has a PME task

Exceptions

std::bad_alloc

If out of memory. InconsistentInputError If user and/or detected inputs are inconsistent.

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The documentation for this class was generated from the following files:

• src/gromacs/taskassignment/taskassignment.h
• src/gromacs/taskassignment/taskassignment.cpp