The BOINC API provides a number of functions, and in developing a compound application you must decide whether these functions are to be performed by the main or worker program. The functions are represented by flags in the BOINC_OPTIONS structure. Each flag must be set in either the main or worker programs, but not both.
struct BOINC_OPTIONS {
int main_program;
int check_heartbeat;
int handle_trickle_ups;
int handle_trickle_downs;
int handle_process_control;
int handle send_status_msgs;
int direct_process_action;
};
int boinc_init_options(BOINC_OPTIONS&);
";
list_start();
list_item("main_program",
"Set this in the main program."
);
list_item("check_heartbeat",
"If set, the program monitors 'heartbeat' messages from the core client.
If the heartbeat stops, the result depends on the direct_process_action
flag (see below)."
);
list_item("handle_trickle_ups",
"If set, the program can send trickle-up messages."
);
list_item("handle_trickle_downs",
"If set, the program can receive trickle-down messages."
);
list_item("handle_process_control",
"If set, the program will handle 'suspend', 'resume', and 'quit'
messages from the core client.
The action depends on the direct_process_action flag."
);
list_item("send_status_msgs",
"If set, the program will report its CPU time and fraction
done to the core client. Set in worker programs."
);
list_item("direct_process_action",
"If set, the program will respond to quit messages and heartbeat
failures by exiting, and will respond to suspend and resume
messages by suspending and resuming.
Otherwise, these events will result in changes to
the BOINC_STATUS structure,
which can be polled using boinc_get_status()."
);
list_end();
echo "
Typical main program logic is:
BOINC_OPTIONS options;
options.main_program = true;
...
boinc_init_options(options)
read main state file
for each remaining worker program:
aid.fraction_done_start = x
aid.fraction_done_end = y
boinc_write_init_data_file()
run the app
wait for the app to finish
poll
write main state file
if last app:
break
boinc_parse_init_data_file() // reads CPU time from app_init.xml file
boinc_finish()
where x and y are the appropriate fraction done range limits.
Typical worker program logic is:
BOINC_OPTIONS options; options.main_program = false; ... boinc_init_options(options); ... do work, calling boinc_fraction_done() with values from 0 to 1, and boinc_time_to_checkpoint(), occasionally ... boinc_finish(); // this writes final CPU time to app_init.xml file
If the graphics is handled in a program that runs concurrently with
the worker programs, it must also call
boinc_init_options(), typically with all options false,
then boinc_init_graphics(),
and eventually boinc_finish().
If the main program is responsible for reporting application status to the core client, it should periodically call
boinc_report_app_status(
double cpu_time, // CPU time since start of WU
double checkpoint_cpu_time, // CPU time at last checkpoint
double fraction_done
);
";
page_tail();
?>