vine: check worker transfer capacity earlier (#4013)

* consider worker transfer capacity in check_worker_against_task

* lint

* fix comment

taskvine/src/manager/vine_manager.c

@@ -3143,7 +3143,7 @@ If a file can be fetched from a substitute source,
 this function modifies the file->substitute field to reflect that source.
 */
 
-static int vine_manager_transfer_capacity_available(struct vine_manager *q, struct vine_worker_info *w, struct vine_task *t)
+int vine_manager_transfer_capacity_available(struct vine_manager *q, struct vine_worker_info *w, struct vine_task *t)
 {
 	struct vine_mount *m;
 
@@ -3324,55 +3324,41 @@ static int vine_manager_check_library_for_function_call(struct vine_manager *q,
 }
 
 /*
-Consider if a task is eligible to run, and if so, find the best worker for it.
+Consider if a task is eligible to run.
 */
-static struct vine_worker_info *consider_task(struct vine_manager *q, struct vine_task *t)
+int consider_task(struct vine_manager *q, struct vine_task *t)
 {
 	timestamp_t now_usecs = timestamp_get();
 	double now_secs = ((double)now_usecs) / ONE_SECOND;
 
 	// Skip task if min requested start time not met.
 	if (t->resources_requested->start > now_secs) {
-		return NULL;
+		return 0;
 	}
 
 	// Skip if this task failed recently
 	if (t->time_when_last_failure + q->transient_error_interval > now_usecs) {
-		return NULL;
+		return 0;
 	}
 
 	// Skip if category already running maximum allowed tasks
 	struct category *c = vine_category_lookup_or_create(q, t->category);
 	if (c->max_concurrent > -1 && c->max_concurrent <= c->vine_stats->tasks_running) {
-		return NULL;
+		return 0;
 	}
 
 	// Skip task if temp input files have not been materialized.
 	if (!vine_manager_check_inputs_available(q, t)) {
-		return NULL;
+		return 0;
 	}
 
-	// Skip function call task if no suitable library template was installed
+	// Skip function call task if no suitable library template was installed.
 	if (!vine_manager_check_library_for_function_call(q, t)) {
-		return NULL;
-	}
-
-	// Find the best worker for the task
-	q->stats_measure->time_scheduling = timestamp_get();
-	struct vine_worker_info *w = vine_schedule_task_to_worker(q, t);
-	if (!w) {
-		return NULL;
-	}
-	q->stats->time_scheduling += timestamp_get() - q->stats_measure->time_scheduling;
-
-	// Check if there is transfer capacity available.
-	if (q->peer_transfers_enabled) {
-		if (!vine_manager_transfer_capacity_available(q, w, t))
-			return NULL;
+		return 0;
 	}
 
-	// All checks passed
-	return w;
+	// All checks passed, task is eligible to run.
+	return 1;
 }
 
 /*
@@ -3385,7 +3371,6 @@ static int send_one_task(struct vine_manager *q)
 {
 	int t_idx;
 	struct vine_task *t;
-	struct vine_worker_info *w = NULL;
 
 	int iter_count = 0;
 	int iter_depth = MIN(priority_queue_size(q->ready_tasks), q->attempt_schedule_depth);
@@ -3406,7 +3391,15 @@ static int send_one_task(struct vine_manager *q)
 	// the priority queue data structure where also invokes priority_queue_rotate_reset.
 	PRIORITY_QUEUE_ROTATE_ITERATE(q->ready_tasks, t_idx, t, iter_count, iter_depth)
 	{
-		w = consider_task(q, t);
+		if (!consider_task(q, t)) {
+			continue;
+		}
+
+		// Find the best worker for the task
+		q->stats_measure->time_scheduling = timestamp_get();
+		struct vine_worker_info *w = vine_schedule_task_to_worker(q, t);
+		q->stats->time_scheduling += timestamp_get() - q->stats_measure->time_scheduling;
+
 		if (w) {
 			priority_queue_remove(q->ready_tasks, t_idx);
 			commit_task_to_worker(q, w, t);

taskvine/src/manager/vine_manager.h

@@ -278,6 +278,9 @@ struct vine_task *vine_manager_no_wait(struct vine_manager *q, const char *tag,
 
 void vine_manager_remove_worker(struct vine_manager *q, struct vine_worker_info *w, vine_worker_disconnect_reason_t reason);
 
+/* Check if the worker is able to transfer the necessary files for this task. */
+int vine_manager_transfer_capacity_available(struct vine_manager *q, struct vine_worker_info *w, struct vine_task *t);
+
 /* The expected format of files created by the resource monitor.*/
 #define RESOURCE_MONITOR_TASK_LOCAL_NAME "vine-task-%d"
 #define RESOURCE_MONITOR_REMOTE_NAME "cctools-monitor"

taskvine/src/manager/vine_schedule.c

@@ -233,6 +233,11 @@ int check_worker_against_task(struct vine_manager *q, struct vine_worker_info *w
 		return 0;
 	}
 
+	/* If the worker has transfer capacity to get this task. */
+	if (q->peer_transfers_enabled && !vine_manager_transfer_capacity_available(q, w, t)) {
+		return 0;
+	}
+
 	/* If the worker doesn't have the features the task requires. */
 	if (t->feature_list) {
 		if (!w->features) {