SCore: scorekvs

SCore KVS (Key Value Space) provides the enough information for cluster computation of a parallel program. User program can get the information of how a cluster is configured and the information of hosts where the program is running. The content of the scorehosts.db(5) file is also vailable via SCore KVS.

Function Documentation

int score_barrier ( void )

The score_barrier() function synchronizes all nodes. When the SCore KVS is updated by calling the scorekvs_put() or scorekvs_remove() function, the change will not be accesible until calling this score_barrier() function.

Returns:: zero is returned if the function succeeds.

int score_get_hostno ( void )

Returns the host number where a process of user program is running.

Returns:: The host number of the host calling this function

int score_get_nhosts ( void )

Returns the number of hosts where the user program is running.

Returns:: The number of hosts

int score_get_nnodes ( void )

Returns the total number of processes.

Returns:: The number of nodes

int score_get_nodeno ( void )

Returns the process number in the total number of processes running with the calling program.

Returns:: The node number of the process calling this function

int score_get_nprocs ( void )

Returns the number of processes on the host where the process of user program is running.

Returns:: The number of processes on the host calling this function

int score_get_procno ( void )

Returns the process number of the calling process on the host where the process of user program is running.

Returns:: The process numer of the process calling this function

int scoreboard_get_value	(	const char *	name,
		const char *	attr,
		char **	valp
	)

Acessing the content of the scorehosts.db(5) file. The output valp is a malloc()ed string. When the accessing attribute has multiple values, then the output is the comma (,) separated string.

Parameters:

`[in]`	name	record name
`[in]`	name	of attribute of the record
`[out]`	value(s)	associated with the key

Returns:: zero is returned if the function succeeds.

See also:: scorehosts.db(5).

int scorekvs_get	(	const char *	key,
		char **	valp
	)

Obtaining the KVS value associated with the specified key.

Parameters:

`[in]`	key	specifying the key of KVS
`[out]`	values	associated with the key (malloc()ed string)

Returns:: zero is returned if the function succeeds.

int scorekvs_get_first	(	char **	key,
		char **	value
	)

This function is used first time to get all the information int the KVS. The rest of the information must be obtained by calling the scorekvs_get_next() function.

Parameters:

`[out]`	key	malloc()ed string of the key
`[out]`	value	malloc()ed string of the value

Returns:: zero is returned if the function succeeds.

int scorekvs_get_next	(	char **	key,
		char **	value
	)

This function is to extract rest of the information in the KVS. The very first extraction must be done by calling the scorekvs_get_first() function.

Parameters:

`[out]`	key	malloc()ed string of the key
`[out]`	value	malloc()ed string of the value

Returns:: zero is returned if the function succeeds.

int scorekvs_hostinfo	(	int	node,
		char **	hostname,
		int *	nprocs
	)

Obtaining the hostname and the number of processes on the specified host.

Parameters:

`[in]`	node	the node number (process number)
`[out]`	hostname	hostname (malloc()ed string)
`[out]`	nprocs	the number of processes on the host

Returns:: zero is returned if the function succeeds.

int scorekvs_put	(	const char *	key,
		const char *	value
	)

Adding the key and value pair into the KVS. To reflect the result of calling this function, the score_barrier() function must be called.

Parameters:

`[in]`	key
`[in]`	value

Returns:: zero is returned if the function succeeds.

See also:: score_barrier()


Files
file	score_kvs.h
int	score_get_nhosts (void)
int	score_get_hostno (void)
int	score_get_nprocs (void)
int	score_get_procno (void)
int	score_get_nnodes (void)
int	score_get_nodeno (void)
int	scoreboard_get_value (const char name, const char attr, char **valp)
int	scorekvs_hostinfo (int node, char *hostname, int nprocs)
int	score_barrier (void)
int	scorekvs_get (const char key, char *valp)
int	scorekvs_put (const char key, const char value)
int	scorekvs_get_first (char key, char value)
int	scorekvs_get_next (char key, char value)

scorekvs

Files

Detailed Description

Function Documentation