ARMCI - Programming Interfaces
ARMCI programming
interfaces are
explained below. This is an up-to-date document that containing all the
supporting ARMCI APIs. There is also a
document
describing the ARMCI design (API corresponding to release 1.0 only) is available in the
PDF format.
Header file
The
interfaces are prototyped in the "armci.h" header file.
1 Initialization and Termination
int ARMCI_Init()
PURPOSE: Initializes the ARMCI. This function must be called before any ARMCI functions.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_Finalize()
PURPOSE: Finalizes the ARMCI. This function must be called after using ARMCI functions.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
void ARMCI_Cleanup()
PURPOSE: Releases any system resources (like System V shmem ids) that
ARMCI can be holding. It is intended to be used before terminating a program
(e.g., by calling MPI_Abort) in case of an error.
void ARMCI_Error(char *message, int code)
Purpose:
Combines the functionality of ARMCI_Cleanup and MPI_Abort, and
it prints (to the stdout and stderr) a user specified message followed
by an integer code.
ARGUMENTS:
message - Message to print out
code - Error code
2 Copy operations using
the generalized I/O vector format
int ARMCI_PutV(armci_giov_t *dsrc_arr, int arr_len, int proc)
PURPOSE:
Generalized I/O vector operation that transfers data
from
the local memory of calling process (source) to the memory of a remote
process (destination).
DATA TYPE:
typedef struct {
void **src_ptr_ar; - Source starting addresses of each data segment.
void **dst_ptr_ar; - Destination starting addresses of each data segment.
int bytes; - The length of each segment in bytes.
int ptr_ar_len; - Number of data segment.
}armci_giov_t;
ARGUMENTS:
dsrc_arr - Array of data (type of armci_giov_t) to be put to remote process.
arr_len - Number of elements in the dsrc_arr.
proc - Remote process ID (destination).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbPutV(armci_giov_t *dsrc_arr,int arr_len,int proc,armci_hdl_t* handle)
PURPOSE:
Generalized Non-Blocking I/O vector operation that transfers
data
from the local memory of the calling process (source) to the memory of
a
remote
process (destination).
DATA TYPE:
typedef struct {
void **src_ptr_ar; - Source starting addresses of each data segment.
void **dst_ptr_ar; - Destination starting addresses of each data segment.
int bytes; - The length of each segment in bytes.
int ptr_ar_len; - Number of data segment.
}armci_giov_t;
ARGUMENTS:
dsrc_arr - Array of data (type of armci_giov_t) to be put to remote process.
arr_len - Number of elements in the dsrc_arr.
proc - Remote process ID (destination).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_GetV(armci_giov_t *dsrc_arr,int arr_len,int proc)
PURPOSE:
Generalized I/O vector blocking operation that
transfers
data from the remote process memory (source) to the calling process
local
memory (destination).
DATA TYPE:
typedef struct {
void **src_ptr_ar; - Source starting addresses of each data segment.
void **dst_ptr_ar; - Destination starting addresses of each data segment.
int bytes; - The length of each segment in bytes.
int ptr_ar_len; - Number of data segment.
}armci_giov_t;
ARGUMENTS:
dsrc_arr - Array of data (type of armci_giov_t) to get from remote process.
arr_len - Number of elements in the dsrc_arr.
proc - Remote process ID (source).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbGetV(armci_giov_t *dsrc_arr,int arr_len,int proc,armci_hdl_t* handle)
PURPOSE:
Generalized Non-blocking I/O vector operation that transfers
data from the remote process memory (source) to the callingprocess
local memory (destination).
DATA TYPE:
typedef struct {
void **src_ptr_ar; - Source starting addresses of each data segment.
void **dst_ptr_ar; - Destination starting addresses of each data segment.
int bytes; - The length of each segment in bytes.
int ptr_ar_len; - Number of data segment.
}armci_giov_t;
ARGUMENTS:
dsrc_arr - Array of data (type of armci_giov_t) to get from remote process.
arr_len - Number of elements in the dsrc_arr.
proc - Remote process ID (source).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
_____________________________________________________________________________
3 Copy operations using the
strided
format
int ARMCI_PutS(void* src_ptr, int src_stride_ar[], void* dst_ptr, int dst_stride_ar[],
int count[], int stride_levels, int proc)
PURPOSE:
Blocking strided operation that transfers data from the
local memory of calling process (source) to the memory of a remote
process (destination).
ARGUMENTS:
src_ptr - Source starting address of the data block to put.
src_stride_arr - Source array of stride distances in bytes.
dst_ptr - Destination starting address to put data.
dst_stride_ar - Destination array of stride distances in bytes.
count - Block size in each dimension. count[0] should be the
number of bytes of contiguous data in leading dimension.
stride_levels - The level of strides.
proc - Remote process ID (destination).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbPutS(void* src_ptr, int src_stride_ar[], void* dst_ptr, int dst_stride_ar[],
int count[], int stride_levels, int proc,armci_hdl_t* handle)
PURPOSE:
Non-blocking strided operation that transfer data
from
the local memory of calling process (source) to the memory of a remote
process (destination).
ARGUMENTS:
src_ptr - Source starting address of the data block to put.
src_stride_arr - Source array of stride distances in bytes.
dst_ptr - Destination starting address to put data.
dst_stride_ar - Destination array of stride distances in bytes.
count - Block size in each dimension. count[0] should be the
number of bytes of contiguous data in leading dimension.
stride_levels - The level of strides.
proc - Remote process ID (destination).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_GetS(void *src_ptr c_ptr, int src_stride_ar[], void* dst_ptr,
int dst_stride_ar[], int count[], int stride_levels, int proc)
PURPOSE:
Blocking strided operation that transfers data
from
the remote process memory (source) to the calling process local
memory
(destination).
ARGUMENTS:
src_ptr - Source starting address of the data block to get.
src_stride_arr - Source array of stride distances in bytes.
dst_ptr - Destination starting address to get data.
dst_stride_arr - Destination array of stride distances in bytes.
count - Block size in each dimension. count[0] should be the
number of bytes of contiguous data in leading dimension.
stride_levels - The level of strides.
proc - Remote process ID (source).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbGetS(void *src_ptr c_ptr, int src_stride_ar[], void* dst_ptr, int dst_stride_ar[],
int count[], int stride_levels, int proc, armci_hdl_t* handle)
PURPOSE:
Non-blocking strided operation that transfers data
from
the remote process memory (source) to the calling process local
memory
(destination).
ARGUMENTS:
src_ptr - Source starting address of the data block to get.
src_stride_arr - Source array of stride distances in bytes.
dst_ptr - Destination starting address to get data.
dst_stride_arr - Destination array of stride distances in bytes.
count - Block size in each dimension. count[0] should be the
number of bytes of contiguous data in leading dimension.
stride_levels - The level of strides.
proc - Remote process ID (source).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
_____________________________________________________________________________
4 Copy operations for contiguous
data
int ARMCI_Put(void* src, void* dst, int bytes, int proc)
PURPOSE: Blocking transfer of contiguous data from
the local process
memory (source) to remote process memory (destination).
ARGUMENTS:
src - Source starting address of the data block to put.
dst - Destination starting address to put data.
bytes - amount of data to transfer in bytes.
proc - Remote process ID (destination).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbPut(void* src, void* dst, int bytes, int proc, armci_hdl_t* handle)
PURPOSE: Non-blocking transfer of contiguous data
from
the local
process
memory (source) to remote process memory (destination).
ARGUMENTS:
src - Source starting address of the data block to put.
dst - Destination starting address to put the data.
bytes - amount of data to transfer in bytes.
proc - Remote process ID (destination).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_Get(src, dst, bytes, proc)
PURPOSE:
Blocking transfer of contiguous data from the remote process
memory (source) to the calling process
memory (destination).
ARGUMENTS:
src - Source starting address of the data block to get.
dst - Destination starting address to get the data.
bytes - amount of data to transfer in bytes.
proc - Remote process ID (destination).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbGet(src, dst, bytes, proc, armci_hdl_t* handle)
PURPOSE:
Non-blocking transfer of contiguous
data
from the remote process memory (source) to the calling process
memory
(destination).
ARGUMENTS:
src - Source starting address of the data block to get.
dst - Destination starting address to get the data.
bytes - amount of data to transfer in bytes.
proc - Remote process ID (destination).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
__________________________________________________________________________
5 Accumulate operation using the
generalized I/O
vector format
Accumulate
operation performs atomic scaled reduction, i.e.,
remote += scale*local
int ARMCI_AccV(int datatype, void *scale, armci_giov_t *dsrc_arr, int arr_len, int proc,
armci_hdl_t* handle)
PURPOSE: Blocking generalized I/O vector operation that atomically updates the memory of
a remote process (destination).
DATA TYPE:
typedef struct {
void **src_ptr_ar; - Source starting addresses of each data segment.
void **dst_ptr_ar; - Destination starting addresses of each data segment.
int bytes; - The length of each segment in bytes.
int ptr_ar_len; - Number of data segment.
}armci_giov_t;
ARGUMENTS:
datatype - Supported data types are:
ARMCI_ACC_INT -> int, ARMCI_ACC_LNG -> long,
ARMCI_ACC_FLT -> float, ARMCI_ACC_DBL-> double,
ARMCI_ACC_CPL -> complex, ARMCI_ACC_DCPL -> double complex.
scale - Scale for the data (dest = dest + scale * src).
dsrc_arr - Array of data (type of armci_giov_t) to be accumulated to the remote process.
arr_len - Number of elements in the dsrc_arr.
proc - Remote process ID.
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbAccV(int datatype, void *scale, armci_giov_t *dsrc_arr, int arr_len, int proc,
armci_hdl_t* handle)
PURPOSE:
Non-blocking generalized I/O vector operation that
atomically
updates the memory of a remote process (destination).
DATA TYPE:
typedef struct {
void **src_ptr_ar; - Source starting addresses of each data segment.
void **dst_ptr_ar; - Destination starting addresses of each data segment.
int bytes; - The length of each segment in bytes.
int ptr_ar_len; - Number of data segment.
}armci_giov_t;
ARGUMENTS:
datatype - Supported data types are:
ARMCI_ACC_INT -> int, ARMCI_ACC_LNG -> long,
ARMCI_ACC_FLT -> float, ARMCI_ACC_DBL-> double,
ARMCI_ACC_CPL -> complex, ARMCI_ACC_DCPL -> double complex.
scale - Scale for the data (dest = dest + scale * src).
dsrc_arr - Array of data (type of armci_giov_t) to be accumulated to the remote process.
arr_len - Number of elements in the dsrc_arr.
proc - Remote process ID.
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
_____________________________________________________________________________
6 Accumulate operation using the
strided format
int ARMCI_AccS(int datatype, void *scale, void* src_ptr,int src_stride_ar[], void* dst_ptr,
int dst_stride_ar[], int count[], int stride_levels, int proc)
PURPOSE: Blocking strided operation that atomicaly updates the memory of a remote process (destination).
ARGUMENTS:
datatype - Supported data types are:
ARMCI_ACC_INT -> int, ARMCI_ACC_LNG -> long,
ARMCI_ACC_FLT -> float, ARMCI_ACC_DBL-> double,
ARMCI_ACC_CPL -> complex, ARMCI_ACC_DCPL -> double complex.
scale - Scale for the data (dest = dest + scale * src).
src_ptr - Source starting address of the data block to put.
src_stride_arr - Source array of stride distances in bytes.
dst_ptr - Destination starting address to put data.
dst_stride_arr - Destination array stride distances in bytes.
count - Block size in each dimension. count[0] should be the
number of bytes of contiguous data in leading dimension.
stride_levels - The level of strides.
proc - Remote process ID (destination).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbAccS(int datatype, void *scale, void* src_ptr,int src_stride_ar[],
void* dst_ptr, int dst_stride_ar[], int count[], int stride_levels,
int proc, armci_hdl_t* handle)
PURPOSE: Non-blocking strided
operation
that atomicaly updates the memory of a remote process (destination).
ARGUMENTS:
datatype - Supported data types are:
ARMCI_ACC_INT -> int, ARMCI_ACC_LNG -> long,
ARMCI_ACC_FLT -> float, ARMCI_ACC_DBL-> double,
ARMCI_ACC_CPL -> complex, ARMCI_ACC_DCPL -> double complex.
scale - Scale for the data (dest = dest + scale * src).
src_ptr - Source starting address of the data block to put.
src_stride_arr - Source array of stride distances in bytes.
dst_ptr - Destination starting address to put data.
dst_stride_arr - Destination array stride distances in bytes.
count - Block size in each dimension. count[0] should be the
number of bytes of contiguous data in leading dimension.
stride_levels - The level of strides.
proc - Remote process ID (destination).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
7 Accumulate operation using
contiguous format
int ARMCI_Acc(int datatype, void *scale, void* src, void* dst, int bytes, int proc)
PURPOSE: Blocking operation that atomicaly updates the memory of a remote process (destination).
ARGUMENTS:
datatype - Supported data types are:
ARMCI_ACC_INT -> int, ARMCI_ACC_LNG -> long,
ARMCI_ACC_FLT -> float, ARMCI_ACC_DBL-> double,
ARMCI_ACC_CPL -> complex, ARMCI_ACC_DCPL -> double complex.
scale - Scale for the data (dest = dest + scale * src).
src - Source starting address of the data to transfer.
dst - Destination starting address to add incoming data.
bytes - amount of data to transfer in bytes.
proc - Remote process ID (destination).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbAcc(int datatype, void *scale, void* src, void* dst, int bytes, int proc,
armci_hdl_t* handle)
PURPOSE: Bon-blocking operation that atomicaly updates the memory of a remote process (destination).
ARGUMENTS:
datatype - Supported data types are:
ARMCI_ACC_INT -> int, ARMCI_ACC_LNG -> long,
ARMCI_ACC_FLT -> float, ARMCI_ACC_DBL-> double,
ARMCI_ACC_CPL -> complex, ARMCI_ACC_DCPL -> double complex.
scale - Scale for the data (dest = dest + scale * src).
src - Source starting address of the data to transfer.
dst - Destination starting address to add incoming data.
bytes - amount of data to transfer in bytes.
proc - Remote process ID (destination).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
_____________________________________________________________________________
8 Register Originated Data Transfer
Operations
int ARMCI_PutValueXXX(DATATYPE src, void* dst, int proc)
PURPOSE: Transfer of a value stored in a
register of a local
process
to remote process memory (destination). XXX can be
"Long"/"Int"/"Double"/"Float"
ARGUMENTS:
DATA TYPE - long, int, float, double according to XXX in the function name
src - Value in a register to put.
dst - Destination starting address to put data.
proc - Remote process ID (destination).
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_NbPutValueXXX(DATATYPE src, void* dst, int proc, armci_hdl_t* handle)
PURPOSE: Non-blocking transfer of a value stored in
a register of a
local
process to remote process memory (destination).
XXX can be "Long"/"Int"/"Double"/"Float"
ARGUMENTS:
DATA TYPE: - long, int, float, double according to XXX in the function name
src - Value in a register to put.
dst - Destination starting address to put data.
proc - Remote process ID (destination).
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
Passing of a NULL value for this arg makes this function do an implicit
handle non-blocking transfer.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
DATATYPE ARMCI_GetValueXXX(void *src, int proc)
PURPOSE: Transfer of a value stored in a
register of a process
(source).
XXX can be "Long"/"Int"/"Double"/"Float"
ARGUMENTS:
DATATYPE - long, int, float, double according to XXX in the function name
src - Source starting address.
proc - Remote process ID (source).
RETURN VALUE:
the value (of type DATATYPE) is returned.
_____________________________________________________________________________
9 Completion of Outstanding
Operations
void ARMCI_Fence(int proc)
PURPOSE: Blocks the calling process until all put or
accumulate
operations
issued to the specified remote process complete at the destination.
ARGUMENTS:
proc - Remote process ID.
void ARMCI_AllFence()
PURPOSE: Blocks the calling process until all the
outstanding
put or accumulate
operations complete remotely regardless of the destination processor.
ARGUMENTS: none
int ARMCI_Wait(armci_hdl_t* handle)
PURPOSE: A common function to be used to wait
for non-blocking
ARMCI
operations with explicit handle.
ARGUMENTS:
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
A value of NULL for the pointer is erroneous. A value other then NULL would
make this routine act as a wait for an explicit non-blocking request with
the handle pointed to by reqid.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_Test(armci_hdl_t* handle)
PURPOSE:
A function to be used as check completion status of
non-blocking
ARMCI operations with explicit handle.
ARGUMENTS:
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
A value of NULL for the pointer is erroneous. A value other then NULL would
make this routine act as a wait for an explicit non-blocking request with
the handle pointed to by reqid.
RETURN VALUE:
zero - Completed
1 - In progress
other value - Error code (described in the release notes).
int ARMCI_WaitProc(int proc)
PURPOSE: Wait for all outstanding non-blocking
operations with implicit
handles to a particular process to finish.
ARGUMENTS:
proc - proc for which all the outstanding non-blocking operations have to be completed.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_WaitAll()
PURPOSE: Wait for all outstanding non-blocking
operations with implicit
handles to finish.
ARGUMENTS: none
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_Barrier()
PURPOSE: Synchronize processors and memory. This operation combines functionality of
MPI_Barrier and ARMCI_AllFence.
ARGUMENTS: none
RETURN VALUE: none
_____________________________________________________________________________
10 Aggregated Data Transfer
Operations
ARMCI_SET_AGGREGATE_HANDLE
(armci_hdl_t*
handle)
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
PURPOSE: Mark a handle as aggregate. This will allow
ARMCI to combine
nonblocking
operations that use that particular handle and process them as a single
operation. In the initial implementation only contiguous puts or gets
could
use aggregate handle. Specifying the same handle for a mix of put anmd
get calls is not allowed i.e., only multiple put or only multiple get
calls
can use the same handle.
ARMCI_UNSET_AGGREGATE_HANDLE
(armci_hdl_t*
handle)
handle - Pointer to a desciptor associated with a particular non-blocking transfer.
PURPOSE: Clears a handle that has been marked as
aggregate.
11
Atomic and
Synchronization
Operations
int ARMCI_Rmw(int op, void *ploc, void *prem, int value, proc)
PURPOSE: Combines atomically the specified
integer value with the
corresponding integer value (int or long) at the remote memory location
and returns the original value found at that location.
ARGUMENTS:
op - Available operations are:
ARMCI_FETCH_AND_ADD -> int
ARMCI_FETCH_AND_ADD_LONG -> long
ARMCI_SWAP -> int
ARMCI_SWAP_LONG ->long
ploc - Pointer to the local memory.
prem - Pointer to the remote memory.
value - Value to be added to the remote memory.
proc - Remote process ID.
int ARMCI_Create_mutexes(int count)
PURPOSE: Collective operation to create sets of
mutexes on individual
processes.
Each process specifies the number of mutexes associated with that
process. The total number of mutexes allocate will be a sum of the
values specified on each process.
ARGUMENTS:
count - number of mutexes allocated on calling process
count=0 means that no mutexes will be associated with that process.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_Destroy_mutexes(void)
PURPOSE: Collective operation to destroy mutex sets
allocated by
ARMCI_Create_mutexes.
ARGUMENTS: none
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
void ARMCI_Lock(int mutex, int proc)
PURPOSE: Acquire the specified mutex on the
specified
process on behalf
of the calling process.
ARGUMENTS:
mutex - Mutex number (0..count-1)
proc - Remote process ID
void ARMCI_Unlock(int mutex, int proc)
PURPOSE: Releas the specified mutex on the specified
process on behalf
of the calling process. The mutex must have been acquired with
ARMCI_Lock.
ARGUMENTS:
mutex - Mutex number (0..count-1)
proc - Remote process ID
12 Memory Management
int ARMCI_Malloc(void* ptr[], armci_size_t bytes)
PURPOSE: Collective operation to allocate memory
that can be used in
the context
of ARMCI copy operations.
ARGUMENTS:
ptr - Pointer array. Each pointer points to the allocated memory of one process.
bytes - The size of allocated memory in bytes.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
void* ARMCI_Malloc_local(armci_size_t bytes)
PURPOSE: Operation (noncollective) to allocate local
memory. This
memory can only be accessed locally. However, using this memory in
ARMCI operations can improve performance on some systems. For example,
on Myrinet or Infiniband, the memory is registered and therefore
suitable for the native RDMA communication.
ARGUMENTS:
bytes - The size of allocated memory in bytes.
RETURN VALUE:
NULL pointer - Failure.
other value - address of newly allocated memory.
int ARMCI_Free(void *address)
PURPOSE: Collective operation to free memory which
was allocated by
ARMCI_Malloc.
ARGUMENTS:
address - pointer to the allocated memory.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
int ARMCI_Free_local(void *address)
PURPOSE: Non-collective operation to free memory
which was allocated by
ARMCI_Malloc_local.
ARGUMENTS:
address - pointer to the allocated memory.
RETURN VALUE:
zero - Successful.
other value - Error code (described in the release notes).
13 Collective Operations
These
operations can be used as an alternative to the collective
operations in a message-passing library ARMCI is running with. The
programmer can use either.
void armci_msg_brdcst(void* buffer, int len, int root)
PURPOSE: broadcast data from process "root" to everybody else.
ARGUMENTS:
buffer - data to broadcast/receive
len - size of the data
root - rank of the sending process
RETURN VALUE: none
void armci_msg_XXXgop(void *x, int n, int type, char* op)
PURPOSE: allreduce operation for int, long, float, double corresponding to XXX is "i"/"l","f","d"
ARGUMENTS:
x - data
n - number of elements
type - data type, one of: ARMCI_INT/ARMCI_LONG/ARMCI_FLOAT/ARMCI_DOUBLE
op - operator, one of: "+","*","min","max","abs"
RETURN VALUE: none
void armci_msg_barrier(void)
PURPOSE: synchronize all processors
ARGUMENTS: none
RETURN VALUE: none
void armci_msg_reduce(void *x, int n, char* op, int type, int root)
PURPOSE: reduce operation
ARGUMENTS:
x - data
len - size of the data
type - data type, one of: ARMCI_INT/ARMCI_LONG/ARMCI_FLOAT/ARMCI_DOUBLE
op - operator, one of: "+","*","min","max","abs"
RETURN VALUE: none
14 System Configuration
These
operations can be used to determine configuration of the system the
application is running on.
The system configuration is described in terms of locality domains. For
example on clusters with SMP nodes, SMP node is one of two locality
domains for a process. The ARMCI header file predefines
ARMCI_DOMAIN_SMP for querying configuration information on clusters
composed of computer nodes with shared memory.
int armci_domain_nprocs(armci_domain_t domain, int id)
PURPOSE: return number of processes/tasks in locality domain represented by id.
ARGUMENTS:
domain - domain name
id - identifier of a node within the locality domain, value < 0 means my node
RETURN VALUE:
< 0 - error
other value - number of processes/tasks (0, ..., armci_domain_count(domain)-1)
int armci_domain_count(armci_domain_t domain)
PURPOSE: return number of nodes in specified locality domain.
ARGUMENTS:
domain - domain name
RETURN VALUE:
< 0 - error
other value - number of nodes
int armci_domain_id(armci_domain_t domain, int glob_proc_id)
PURPOSE: return ID of locality domain of specified process
ARGUMENTS:
domain - domain name
id - process/task id
RETURN VALUE
< 0 - error
other value - process/task id
int armci_domain_glob_proc_id(armci_domain_t domain, int id, int loc_proc_id)
PURPOSE: Returns
global process/task id based on its id in a given locality domain node
ARGUMENTS:
domain - domain name
id - identifier of a node within the locality
domain, value < 0 means my node
RETURN VALUE:
< 0 - error
other value - process/task id
int armci_domain_my_id(armci_domain_t domain) PURPOSE: Returns id node in specified domain the calling process/task belongs to
ARGUMENTS:
domain - domain name
id - identifier of a node within the locality domain, value < 0 means my node
RETURN VALUE: id of domain
|