--- linux-2.6.0-test7-base/include/linux/sched.h	2003-10-12 22:34:09.000000000 +1000
+++ linux-2.6.0-test7/include/linux/sched.h	2003-10-12 20:46:55.000000000 +1000
@@ -126,6 +126,7 @@ extern unsigned long nr_iowait(void);
 #define SCHED_NORMAL		0
 #define SCHED_FIFO		1
 #define SCHED_RR		2
+#define SCHED_BATCH		3
 
 struct sched_param {
 	int sched_priority;
@@ -294,6 +295,7 @@ struct signal_struct {
 #define MAX_PRIO		(MAX_RT_PRIO + 40)
 
 #define rt_task(p)		((p)->prio < MAX_RT_PRIO)
+#define batch_task(p)		((p)->policy == SCHED_BATCH)
 
 /*
  * Some day this will be a full-fledged user tracking system..
--- linux-2.6.0-test7-base/kernel/sched.c	2003-10-12 22:34:09.000000000 +1000
+++ linux-2.6.0-test7/kernel/sched.c	2003-10-12 23:07:45.000000000 +1000
@@ -153,8 +153,13 @@
 #define LOW_CREDIT(p) \
 	((p)->interactive_credit < -CREDIT_LIMIT)
 
+/*
+ * Batch tasks are preempted by any priority normal tasks.
+ */
 #define TASK_PREEMPTS_CURR(p, rq) \
-	((p)->prio < (rq)->curr->prio)
+	((((p)->prio < (rq)->curr->prio) && (!batch_task(p) || \
+		(batch_task(p) && batch_task((rq)->curr)))) || \
+			(!batch_task(p) && batch_task((rq)->curr)))
 
 /*
  * BASE_TIMESLICE scales user-nice values [ -20 ... 19 ]
@@ -172,6 +177,12 @@
 
 static inline unsigned int task_timeslice(task_t *p)
 {
+	/*
+	 * Batch tasks get much longer timeslices
+	 */
+	if (unlikely(batch_task(p)))
+		return BASE_TIMESLICE(p) * 10;
+
 	return BASE_TIMESLICE(p);
 }
 
@@ -359,7 +370,10 @@ static int effective_prio(task_t *p)
 	if (rt_task(p))
 		return p->prio;
 
-	bonus = CURRENT_BONUS(p) - MAX_BONUS / 2;
+	if (unlikely(batch_task(p)))
+		bonus = 0;
+	else
+		bonus = CURRENT_BONUS(p) - MAX_BONUS / 2;
 
 	prio = p->static_prio - bonus;
 	if (prio < MAX_RT_PRIO)
@@ -374,7 +388,14 @@ static int effective_prio(task_t *p)
  */
 static inline void __activate_task(task_t *p, runqueue_t *rq)
 {
-	enqueue_task(p, rq->active);
+	/*
+	 * Batch tasks get activated onto the expired array.
+	 */
+	if (unlikely(batch_task(p)))
+		enqueue_task(p, rq->expired);
+	else
+		enqueue_task(p, rq->active);
+
 	nr_running_inc(rq);
 }
 
@@ -1408,10 +1429,14 @@ void scheduler_tick(int user_ticks, int 
 		p->time_slice = task_timeslice(p);
 		p->first_time_slice = 0;
 
-		if (!rq->expired_timestamp)
+		if (!rq->expired_timestamp && !batch_task(p))
 			rq->expired_timestamp = jiffies;
-		if (!TASK_INTERACTIVE(p) || EXPIRED_STARVING(rq)) {
-			enqueue_task(p, rq->expired);
+		/*
+		 * Batch tasks are always expired.
+		 */
+		if (batch_task(p) || !TASK_INTERACTIVE(p) ||
+			EXPIRED_STARVING(rq)) {
+				enqueue_task(p, rq->expired);
 		} else
 			enqueue_task(p, rq->active);
 	} else {
@@ -2015,8 +2040,8 @@ static int setscheduler(pid_t pid, int p
 	else {
 		retval = -EINVAL;
 		if (policy != SCHED_FIFO && policy != SCHED_RR &&
-				policy != SCHED_NORMAL)
-			goto out_unlock;
+			policy != SCHED_NORMAL && policy !=SCHED_BATCH)
+				goto out_unlock;
 	}
 
 	/*
@@ -2026,8 +2051,9 @@ static int setscheduler(pid_t pid, int p
 	retval = -EINVAL;
 	if (lp.sched_priority < 0 || lp.sched_priority > MAX_USER_RT_PRIO-1)
 		goto out_unlock;
-	if ((policy == SCHED_NORMAL) != (lp.sched_priority == 0))
-		goto out_unlock;
+	if ((policy == SCHED_NORMAL || policy == SCHED_BATCH) !=
+		(lp.sched_priority == 0))
+			goto out_unlock;
 
 	retval = -EPERM;
 	if ((policy == SCHED_FIFO || policy == SCHED_RR) &&
@@ -2048,7 +2074,7 @@ static int setscheduler(pid_t pid, int p
 	p->policy = policy;
 	p->rt_priority = lp.sched_priority;
 	oldprio = p->prio;
-	if (policy != SCHED_NORMAL)
+	if (policy != SCHED_NORMAL && policy != SCHED_BATCH)
 		p->prio = MAX_USER_RT_PRIO-1 - p->rt_priority;
 	else
 		p->prio = p->static_prio;
@@ -2353,6 +2379,7 @@ asmlinkage long sys_sched_get_priority_m
 		ret = MAX_USER_RT_PRIO-1;
 		break;
 	case SCHED_NORMAL:
+	case SCHED_BATCH:
 		ret = 0;
 		break;
 	}
@@ -2376,6 +2403,7 @@ asmlinkage long sys_sched_get_priority_m
 		ret = 1;
 		break;
 	case SCHED_NORMAL:
+	case SCHED_BATCH:
 		ret = 0;
 	}
 	return ret;