diff --git a/lib/ftl/ftl_core.c b/lib/ftl/ftl_core.c
index 1c3b56c36..1436690c5 100644
--- a/lib/ftl/ftl_core.c
+++ b/lib/ftl/ftl_core.c
@@ -769,8 +769,7 @@ static void
 ftl_wptr_pad_band(struct ftl_wptr *wptr)
 {
 	struct spdk_ftl_dev *dev = wptr->dev;
-	size_t size = ftl_rwb_num_acquired(dev->rwb, FTL_RWB_TYPE_INTERNAL) +
-		      ftl_rwb_num_acquired(dev->rwb, FTL_RWB_TYPE_USER);
+	size_t size = ftl_rwb_num_pending(dev->rwb);
 	size_t blocks_left, rwb_size, pad_size;
 
 	blocks_left = ftl_wptr_user_lbks_left(wptr);
@@ -787,8 +786,7 @@ static void
 ftl_wptr_process_shutdown(struct ftl_wptr *wptr)
 {
 	struct spdk_ftl_dev *dev = wptr->dev;
-	size_t size = ftl_rwb_num_acquired(dev->rwb, FTL_RWB_TYPE_INTERNAL) +
-		      ftl_rwb_num_acquired(dev->rwb, FTL_RWB_TYPE_USER);
+	size_t size = ftl_rwb_num_pending(dev->rwb);
 	size_t num_active = dev->xfer_size * ftl_rwb_get_active_batches(dev->rwb);
 
 	num_active = num_active ? num_active : dev->xfer_size;
diff --git a/lib/ftl/ftl_rwb.c b/lib/ftl/ftl_rwb.c
index 854c9ae23..20e098c13 100644
--- a/lib/ftl/ftl_rwb.c
+++ b/lib/ftl/ftl_rwb.c
@@ -83,6 +83,8 @@ struct ftl_rwb {
 
 	/* Number of acquired entries */
 	unsigned int				num_acquired[FTL_RWB_TYPE_MAX];
+	/* Number of acquired but not yet submitted entries */
+	unsigned int				num_pending;
 	/* User/internal limits */
 	size_t					limits[FTL_RWB_TYPE_MAX];
 
@@ -302,7 +304,7 @@ ftl_rwb_batch_release(struct ftl_rwb_batch *batch)
 		num_acquired = __atomic_fetch_sub(&rwb->num_acquired[ftl_rwb_entry_type(entry)], 1,
 						  __ATOMIC_SEQ_CST);
 		entry->band = NULL;
-		assert(num_acquired  > 0);
+		assert(num_acquired > 0);
 	}
 
 	pthread_spin_lock(&rwb->lock);
@@ -371,6 +373,14 @@ ftl_rwb_batch_revert(struct ftl_rwb_batch *batch)
 	if (spdk_ring_enqueue(rwb->prio_queue, (void **)&batch, 1, NULL) != 1) {
 		assert(0 && "Should never happen");
 	}
+
+	__atomic_fetch_add(&rwb->num_pending, rwb->xfer_size, __ATOMIC_SEQ_CST);
+}
+
+unsigned int
+ftl_rwb_num_pending(struct ftl_rwb *rwb)
+{
+	return __atomic_load_n(&rwb->num_pending, __ATOMIC_SEQ_CST);
 }
 
 void
@@ -457,6 +467,7 @@ ftl_rwb_acquire(struct ftl_rwb *rwb, enum ftl_rwb_entry_type type)
 
 	pthread_spin_unlock(&rwb->lock);
 	__atomic_fetch_add(&rwb->num_acquired[type], 1, __ATOMIC_SEQ_CST);
+	__atomic_fetch_add(&rwb->num_pending, 1, __ATOMIC_SEQ_CST);
 	return entry;
 error:
 	pthread_spin_unlock(&rwb->lock);
@@ -491,12 +502,19 @@ struct ftl_rwb_batch *
 ftl_rwb_pop(struct ftl_rwb *rwb)
 {
 	struct ftl_rwb_batch *batch = NULL;
+	unsigned int num_pending __attribute__((unused));
 
 	if (spdk_ring_dequeue(rwb->prio_queue, (void **)&batch, 1) == 1) {
+		num_pending = __atomic_fetch_sub(&rwb->num_pending, rwb->xfer_size,
+						 __ATOMIC_SEQ_CST);
+		assert(num_pending > 0);
 		return batch;
 	}
 
 	if (spdk_ring_dequeue(rwb->submit_queue, (void **)&batch, 1) == 1) {
+		num_pending = __atomic_fetch_sub(&rwb->num_pending, rwb->xfer_size,
+						 __ATOMIC_SEQ_CST);
+		assert(num_pending > 0);
 		return batch;
 	}
 
diff --git a/lib/ftl/ftl_rwb.h b/lib/ftl/ftl_rwb.h
index ead170c59..cc7e0f1a9 100644
--- a/lib/ftl/ftl_rwb.h
+++ b/lib/ftl/ftl_rwb.h
@@ -118,6 +118,7 @@ struct ftl_rwb_entry *ftl_rwb_batch_first_entry(struct ftl_rwb_batch *batch);
 void	*ftl_rwb_batch_get_data(struct ftl_rwb_batch *batch);
 void	*ftl_rwb_batch_get_md(struct ftl_rwb_batch *batch);
 void	ftl_rwb_disable_interleaving(struct ftl_rwb *rwb);
+unsigned int ftl_rwb_num_pending(struct ftl_rwb *rwb);
 
 static inline void
 _ftl_rwb_entry_set_valid(struct ftl_rwb_entry *entry, bool valid)