vt::group::GroupManager struct
#include <src/vt/group/group_manager.h>

A core VT component that can create and manage groups of nodes.

Enables rooted and collective asynchronous construction of groups of nodes. The default group is all the nodes in the communicator, which is the group a normal broadcast targets. Beyond this, both the VT system and users can dynamically create groups in a fully distributed manner.

Base classes

template<typename T> struct vt::runtime::component::Component<GroupManager>: Component class for a generic VT runtime module, CRTP'ed over the component's actual type

Derived classes

template<typename T> struct GroupManagerT: Group manager that handles typed actions that are registered for system use.

Public types

using RegionType = region::Region
using RegionPtrType = std::unique_ptr<RegionType>
using GroupInfoType = Info
using GroupInfoPtrType = std::unique_ptr<GroupInfoType>
using GroupContainerType = std::unordered_map<GroupType, GroupInfoPtrType>
using ActionGroupType = std::function<void(GroupType)>
using TreeType = collective::tree::Tree
using TreePtrType = std::unique_ptr<TreeType>
using ActionListType = std::vector<ActionType>
using ActionContainerType = std::unordered_map<RemoteOperationIDType, ActionListType>
using ReduceType = collective::reduce::Reduce
using ReducePtrType = ReduceType*
using CollectiveScopeType = collective::CollectiveScope

Constructors, destructors, conversion operators

GroupManager(): Construct the GroupManager.
~GroupManager() virtual

Public functions

auto name() -> std::string override: Get the name of the component.
void setupDefaultGroup(): Setup the default group spanning all nodes. Called by the VT system at startup so broadcasts can take place.
void AddNewTempGroup(const region::Region::ListType& range, GroupType group): Cache group created by multicast. This allows for reusing the same group.
auto GetTempGroupForRange(const region::Region::ListType& range) -> std::optional<GroupType>: Return (if any) group associated with given range of nodes.
auto newGroup(RegionPtrType in_region, bool const is_static, ActionGroupType action) -> GroupType: Create a new rooted group.
auto newGroup(RegionPtrType in_region, ActionGroupType action) -> GroupType: Create a new rooted group.
auto newGroupCollective(bool const in_group, ActionGroupType action, bool make_mpi_group = false) -> GroupType: Create a group collectively, must be called on all nodes.
void deleteGroupCollective(GroupType group_id): Delete an existing group that is no longer needed.
auto newGroupCollectiveLabel(GroupCollectiveLabelTagType) -> GroupType: Generate the next group ID.
auto inGroup(GroupType const group) -> bool: Query whether this node is part of a group.
auto getGroupComm(GroupType const group_id) -> MPI_Comm: Get MPI_Comm from VT group.
template<typename MsgT, ActiveTypedFnType<MsgT>* f> void sendMsg(GroupType const group, MsgT* msg)
template<auto f> void sendMsg(GroupType const group, typename FuncTraits<decltype(f)>::MsgT* msg)
auto groupReducer(GroupType const group) -> ReducePtrType: Get the reducer associated with a group to reduce over it.
auto groupRoot(GroupType const group) const -> NodeType: Get the root node for a group.
auto isGroupDefault(GroupType const group) const -> bool: Check if a group is the default group (all nodes, default spanning tree)
void addCleanupAction(ActionType action): Add a cleanup action.
auto getNextOpID() -> RemoteOperationIDType: Get the next operation ID.
template<typename SerializerT> void serialize(SerializerT& s)

Function documentation

void vt::group::GroupManager::AddNewTempGroup(const region::Region::ListType& range, GroupType group)

Cache group created by multicast. This allows for reusing the same group.

Parameters
range in	list of nodes that are part of given group
group in	group to cache

GroupType vt::group::GroupManager::newGroup(RegionPtrType in_region, bool const is_static, ActionGroupType action)

Create a new rooted group.

Parameters
in_region in	list of nodes to include
is_static in	whether the group is static after creation
action in	action to execute when group is finished construction
Returns	the group ID

GroupType vt::group::GroupManager::newGroup(RegionPtrType in_region, ActionGroupType action)

Create a new rooted group.

Parameters
in_region in	list of nodes to include
action in	action to execute when group is finished construction
Returns	the group ID

GroupType vt::group::GroupManager::newGroupCollective(bool const in_group, ActionGroupType action, bool make_mpi_group = false)

Create a group collectively, must be called on all nodes.

Parameters
in_group in	whether this node is included the new group
action in	action to execute when group is finished construction
make_mpi_group in	whether VT should create an underlying MPI group
Returns	the group ID

void vt::group::GroupManager::deleteGroupCollective(GroupType group_id)

Delete an existing group that is no longer needed.

Parameters
group_id in	the id for the group

GroupType vt::group::GroupManager::newGroupCollectiveLabel(GroupCollectiveLabelTagType)

Generate the next group ID.

Returns	the group ID

bool vt::group::GroupManager::inGroup(GroupType const group)

Query whether this node is part of a group.

Parameters
group in	the group ID
Returns	whether this node is included

MPI_Comm vt::group::GroupManager::getGroupComm(GroupType const group_id)

Get MPI_Comm from VT group.

Parameters
group_id in	the group ID
Returns	the MPI_Comm associated with the group; or the default communicator if none.

ReducePtrType vt::group::GroupManager::groupReducer(GroupType const group)

Get the reducer associated with a group to reduce over it.

Parameters
group in	the group ID
Returns	pointer to the reducer

NodeType vt::group::GroupManager::groupRoot(GroupType const group) const

Get the root node for a group.

Parameters
group in	the group ID
Returns	the root node

bool vt::group::GroupManager::isGroupDefault(GroupType const group) const

Check if a group is the default group (all nodes, default spanning tree)

Parameters
group in	the group ID
Returns	whether it is the default group

void vt::group::GroupManager::addCleanupAction(ActionType action)

Add a cleanup action.

Parameters
action in	the action

RemoteOperationIDType vt::group::GroupManager::getNextOpID()

Get the next operation ID.

Returns	the operation ID

vt::group::GroupManager struct #include <src/vt/group/group_manager.h>