Global Dynamic Memory Concept

Concept of distributed dynamic global memory space shared by units in a specified team. More...

Classes
class	dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >
	Global memory region with dynamic size. More...

Functions
	dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::GlobHeapMem (size_type n_local_elem=0)
	Constructor, collectively allocates the given number of elements in local memory of every unit in dash::Team::All(). More...
	dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::GlobHeapMem (size_type n_local_elem, dash::Team &team)
	Constructor, collectively allocates the given number of elements in local memory of every unit in a team. More...
	dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::GlobHeapMem (size_type n_local_elem, LocalMemorySpace *r)
	Constructor, collectively allocates the given number of elements in local memory of every unit in dash::Team::All(). More...

Detailed Description

Concept of distributed dynamic global memory space shared by units in a specified team.

Description

Extends the Global Memory concept by dynamic address spaces.

Units can change the capacity of the global memory space by resizing their own local segment of the global memory space. Resizing local memory segments (methods resize, grow and shrink) is non-collective, however the resulting changes to local and global memory space are only immediately visible to the unit that executed the resize operation.

The collective operation commit synchronizes changes on local memory spaces between all units such that new allocated memory segments are attached in global memory and deallocated segments detached, respectively.

Newly allocated memory segments are unattached and immediately accessible by the local unit only. Deallocated memory is immediately removed from the local unit's memory space but remains accessible for remote units.

Different from typical dynamic container semantics, neither resizing the memory space nor commit operations invalidate iterators to elements in allocated global memory. An iterators referencing a remote element in global dynamic memory is only invalidated in the commit operation following the deallocation of the element's memory segment.

Types

Type Name	Description
GlobalRAI	Random access iterator on global address space
LocalRAI	Random access iterator on a single local address space

Methods

Return Type	Method	Parameters	Description
void	resize	size lsize_new	Resize the local segment of the global memory space to the specified number of values.
void	grow	size lsize_diff	Extend the size of the local segment of the global memory space by the specified number of values.
void	shrink	size lsize_diff	Reduce the size of the local segment of the global memory space by the specified number of values.
void	commit	nbsp;	Publish changes to local memory across all units.

Methods inherited from Global Memory concept

Return Type	Method	Parameters	Description
GlobalRAI	begin		Global pointer to the initial address of the global memory space
GlobalRAI	end		Global pointer past the final element in the global memory space
LocalRAI	lbegin		Local pointer to the initial address in the local segment of the global memory space
LocalRAI	lbegin	unit u	Local pointer to the initial address in the local segment at unit u of the global memory space
LocalRAI	lend		Local pointer past the final element in the local segment of the global memory space
LocalRAI	lend	unit u	Local pointer past the final element in the local segment at unit u of the global memory space
GlobalRAI	at	index gidx	Global pointer to the element at canonical global offset gidx in the global memory space
void	put_value	value & v_in, index gidx	Stores value specified in parameter v_in to address in global memory at canonical global offset gidx
void	get_value	value * v_out, index gidx	Loads value from address in global memory at canonical global offset gidx into local address v_out
void	barrier		Blocking synchronization of all units associated with the global memory instance

Function Documentation

GlobHeapMem() [1/3]

template<typename ElementType , class LocalMemorySpace = dash::HostSpace, global_allocation_policy AllocationPolicy = global_allocation_policy::epoch_synchronized, template< class > class LocalAlloc = allocator::DefaultAllocator>

dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::GlobHeapMem ( size_type  n_local_elem = 0 )

inline

#include </tmp/tmporruphar/dash/include/dash/memory/GlobHeapMem.h>

Constructor, collectively allocates the given number of elements in local memory of every unit in dash::Team::All().

Implemented concept:

Global Dynamic Memory Concept

Implemented concept:

DashMemorySpaceConcept

Parameters

n_local_elem

Initial number of local elements to allocate in global memory space

Definition at line 308 of file GlobHeapMem.h.

    : GlobHeapMem(n_local_elem, nullptr)
  {
  }

GlobHeapMem() [2/3]

template<typename ElementType , class LocalMemorySpace = dash::HostSpace, global_allocation_policy AllocationPolicy = global_allocation_policy::epoch_synchronized, template< class > class LocalAlloc = allocator::DefaultAllocator>

dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::GlobHeapMem ( size_type  n_local_elem, dash::Team &  team  )

inline

#include </tmp/tmporruphar/dash/include/dash/memory/GlobHeapMem.h>

Constructor, collectively allocates the given number of elements in local memory of every unit in a team.

Implemented concept:

Global Dynamic Memory Concept

Implemented concept:

DashMemorySpaceConcept

Parameters

n_local_elem	Initial number of local elements to allocate in global memory space
team	The specified team

Definition at line 322 of file GlobHeapMem.h.

    : GlobHeapMem(n_local_elem, nullptr, team)
  {
  }

GlobHeapMem() [3/3]

template<typename ElementType , class LocalMemorySpace = dash::HostSpace, global_allocation_policy AllocationPolicy = global_allocation_policy::epoch_synchronized, template< class > class LocalAlloc = allocator::DefaultAllocator>

dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::GlobHeapMem ( size_type  n_local_elem, LocalMemorySpace *  r  )

inline

#include </tmp/tmporruphar/dash/include/dash/memory/GlobHeapMem.h>

Constructor, collectively allocates the given number of elements in local memory of every unit in dash::Team::All().

The underlying memory space is specified by the resource which is passed in

Implemented concept:

Global Dynamic Memory Concept

Implemented concept:

DashMemorySpaceConcept

Parameters

n_local_elem	Initial number of local elements to allocate in global memory space
r	The underlying local memory space

Definition at line 339 of file GlobHeapMem.h.

References dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::commit(), dash::Team::dart_id(), dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::grow(), dash::Array< ElementType, IndexType, PatternType, LocalMemSpaceT >::local, dash::Team::size(), and dash::GlobHeapMem< ElementType, LocalMemorySpace, AllocationPolicy, LocalAlloc >::team().

    : GlobHeapMem(n_local_elem, r, dash::Team::All())
  {
  }