diff --git a/processor.go b/processor.go
index 87a3570..71770cb 100644
--- a/processor.go
+++ b/processor.go
@@ -81,31 +81,12 @@ func (p *processor) exec() {
 	task := &Task{Type: msg.Type, Payload: msg.Payload}
 	p.sema <- struct{}{} // acquire token
 	go func(task *Task) {
-		quit := make(chan struct{}) // channel to signal heartbeat goroutine
 		defer func() {
-			quit <- struct{}{}
 			if err := p.rdb.srem(inProgress, msg); err != nil {
 				log.Printf("[SERVER ERROR] SREM failed: %v\n", err)
 			}
-			if err := p.rdb.clearHeartbeat(msg.ID); err != nil {
-				log.Printf("[SERVER ERROR] DEL heartbeat failed: %v\n", err)
-			}
 			<-p.sema // release token
 		}()
-		// start "heartbeat" goroutine
-		go func() {
-			ticker := time.NewTicker(5 * time.Second)
-			for {
-				select {
-				case <-quit:
-					return
-				case t := <-ticker.C:
-					if err := p.rdb.heartbeat(msg.ID, t); err != nil {
-						log.Printf("[ERROR] heartbeat failed for %v at %v: %v", msg.ID, t, err)
-					}
-				}
-			}
-		}()
 		err := p.handler(task) // TODO(hibiken): maybe also handle panic?
 		if err != nil {
 			retryTask(p.rdb, msg, err)
diff --git a/rdb.go b/rdb.go
index d4e00e7..5a4b692 100644
--- a/rdb.go
+++ b/rdb.go
@@ -9,7 +9,6 @@ import (
 	"time"
 
 	"github.com/go-redis/redis/v7"
-	"github.com/google/uuid"
 )
 
 // Redis keys
@@ -147,24 +146,6 @@ func (r *rdb) move(from string, msg *taskMessage) error {
 	return nil
 }
 
-func (r *rdb) heartbeat(id uuid.UUID, timestamp time.Time) error {
-	key := heartbeatPrefix + id.String()
-	err := r.client.Set(key, timestamp, 0).Err() // zero expiration means no expiration
-	if err != nil {
-		return fmt.Errorf("command SET %s %v failed: %v", key, timestamp, err)
-	}
-	return nil
-}
-
-func (r *rdb) clearHeartbeat(id uuid.UUID) error {
-	key := heartbeatPrefix + id.String()
-	err := r.client.Del(key).Err()
-	if err != nil {
-		return fmt.Errorf("command DEL %s failed: %v", key, err)
-	}
-	return nil
-}
-
 const maxDeadTask = 100
 const deadExpirationInDays = 90