For scalability reasons, when a job array is submitted only one job
record is created. As individual tasks in the job array start running,
a new job record is created for each task. The relevant parts in the
job record (from slurm.h) are:
uint32_t array_job_id; /* job_id of a job array or 0 if N/A */
uint32_t array_task_id; /* task_id of a job array */
uint32_t array_max_tasks; /* Maximum number of running tasks */
char *array_task_str; /* string expression of task IDs in this record
*/
Here's the code from src/api/job_info.c that demonstrates how to use
that information:
if (job_ptr->array_job_id) {
if (job_ptr->array_task_str) {
snprintf(tmp_line, sizeof(tmp_line),
"ArrayJobId=%u ArrayTaskId=%s ",
job_ptr->array_job_id,
job_ptr->array_task_str);
} else {
snprintf(tmp_line, sizeof(tmp_line),
"ArrayJobId=%u ArrayTaskId=%u ",
job_ptr->array_job_id,
job_ptr->array_task_id);
}
xstrcat(out, tmp_line);
}
Quoting E V <[email protected]>:
Trying drmaa with slurm > 14.03 using job arrays for the first time.
Doesn't work.
The drmaa code in session.c:slurmdrmaa_session_run_bulk() successfully
submits my 2-job array(via slurm_submit_batch_job().) However, it
calls slurm_load_job(&job_info,...) and expects job_info->record_count
to be == the number of jobs in the array in order to iterate and
create jobs for all the jobs in the array (via slurmdrmaa_job_new().)
I guess this behaviour has changed in 14.11+, because record_count is
now == 1. I see this new job_array_resp_msg_t type, but I don't see a
corresponding load_job function in slurm.h using it. How does the
handling of job arrays work now in slurm >14.03?
--
Morris "Moe" Jette
CTO, SchedMD LLC
Commercial Slurm Development and Support
===============================================================
Slurm User Group Meeting, 15-16 September 2015, Washington D.C.
http://slurm.schedmd.com/slurm_ug_agenda.html
