diff --git a/src/CraneCtld/TaskScheduler.cpp b/src/CraneCtld/TaskScheduler.cpp
index 355627d47..e57a8ea22 100644
--- a/src/CraneCtld/TaskScheduler.cpp
+++ b/src/CraneCtld/TaskScheduler.cpp
@@ -2081,53 +2081,43 @@ bool MinLoadFirst::CalculateRunningNodesAndStartTime_(
   for (CranedId craned_id : craned_indexes_) {
     auto& time_avail_res_map =
         node_selection_info.node_time_avail_res_map.at(craned_id);
-    auto it = time_avail_res_map.begin();
-    trackers.emplace_back(craned_id, it, time_avail_res_map.end(),
+    trackers.emplace_back(craned_id, time_avail_res_map.begin(),
+                          time_avail_res_map.end(),
                           &task->Resources().at(craned_id));
     pq.emplace(&trackers.back());
   }
 
-  int satisfied_count = 0;
-  absl::Time last_time = absl::InfinitePast();
+  TrackerList satisfied_trackers(task->node_num);
+
   while (!pq.empty()) {
     absl::Time time = pq.top()->it->first;
     if (time - now > kAlgoMaxTimeWindow) {
       return false;
     }
     while (!pq.empty() && pq.top()->it->first == time) {
-      auto tmp = pq.top();
+      auto tracker = pq.top();
       pq.pop();
-      satisfied_count -= tmp->satisfied;
-      if (tmp->genNext()) pq.emplace(tmp);
-      satisfied_count += tmp->satisfied;
-    }
-    if constexpr (kAlgoTraceOutput) {
-      CRANE_TRACE("At time now+{}s, {} nodes are satisfied.",
-                  (time - now) / absl::Seconds(1), satisfied_count);
-      for (auto& tracker : trackers) {
-        if (tracker.satisfied) {
-          CRANE_TRACE("Craned {} is satisfied.", tracker.craned_id);
-        }
+      if (tracker->satisfied()) {
+        satisfied_trackers.try_push_back(tracker, time);
+      } else {
+        satisfied_trackers.try_erase(tracker);
       }
-    }
-    if (satisfied_count < task->node_num) {
-      last_time = absl::InfinitePast();
-    } else {
-      if (last_time == absl::InfinitePast()) {
-        last_time = time;
+      if (tracker->genNext()) {
+        pq.emplace(tracker);
       }
-      if (time - last_time >= task->time_limit || pq.empty()) {
-        *start_time = last_time;
-        craned_ids->clear();
-        for (auto& tracker : trackers) {
-          if (tracker.satisfied) {
-            craned_ids->emplace_back(tracker.craned_id);
-            if (craned_ids->size() >= task->node_num) break;
-          }
-        }
-        CRANE_ASSERT(craned_ids->size() == task->node_num);
-        return true;
+    }
+    if (pq.empty() || satisfied_trackers.kth_time() + task->time_limit <=
+                          pq.top()->it->first) {
+      *start_time = satisfied_trackers.kth_time();
+      craned_ids->clear();
+      auto it = satisfied_trackers.kth_elem;
+      while (it != nullptr) {
+        craned_ids->emplace_back(it->tracker_ptr->craned_id);
+        it = it->prev;
       }
+      CRANE_ASSERT(*start_time != absl::InfiniteFuture());
+      CRANE_ASSERT(craned_ids->size() == task->node_num);
+      return true;
     }
   }
 
diff --git a/src/CraneCtld/TaskScheduler.h b/src/CraneCtld/TaskScheduler.h
index 1a19a08b7..fb5c88e7e 100644
--- a/src/CraneCtld/TaskScheduler.h
+++ b/src/CraneCtld/TaskScheduler.h
@@ -164,7 +164,7 @@ class MinLoadFirst : public INodeSelectionAlgo {
     TimeAvailResMap::const_iterator it;
     const TimeAvailResMap::const_iterator end;
     const ResourceInNode* task_res;
-    bool satisfied;
+    void* tracker_list_elem;
 
     TimeAvailResTracker(const CranedId& craned_id,
                         const TimeAvailResMap::const_iterator& begin,
@@ -174,11 +174,71 @@ class MinLoadFirst : public INodeSelectionAlgo {
           it(begin),
           end(end),
           task_res(task_res),
-          satisfied(false) {}
+          tracker_list_elem(nullptr) {}
 
-    bool genNext() {
-      satisfied = *task_res <= it->second;
-      return ++it != end;
+    bool satisfied() const { return *task_res <= it->second; }
+
+    bool genNext() { return ++it != end; }
+  };
+
+  struct TrackerList {
+    struct TrackerListElem {
+      TimeAvailResTracker* tracker_ptr;
+      absl::Time time;
+      TrackerListElem* prev;
+      TrackerListElem* next;
+      bool first_k;
+    };
+
+    size_t size;
+    int node_num;
+    TrackerListElem* tail;
+    TrackerListElem* kth_elem;
+
+    TrackerList(int node_num)
+        : size(0), node_num(node_num), tail(nullptr), kth_elem(nullptr) {}
+
+    void try_push_back(TimeAvailResTracker* it, absl::Time time) {
+      if (it->tracker_list_elem) return;
+      TrackerListElem* elem =
+          new TrackerListElem{it, time, nullptr, nullptr, ++size <= node_num};
+      if (tail) {
+        elem->prev = tail;
+        tail->next = elem;
+      }
+      if (size == node_num) {
+        kth_elem = elem;
+      }
+      tail = elem;
+      it->tracker_list_elem = elem;
+    }
+
+    void try_erase(TimeAvailResTracker* it) {
+      TrackerListElem* elem =
+          static_cast<TrackerListElem*>(it->tracker_list_elem);
+      if (!elem) return;
+      if (elem->first_k && kth_elem) {
+        kth_elem = kth_elem->next;
+        if (kth_elem) {
+          kth_elem->first_k = true;
+        }
+      }
+      if (elem->prev) {
+        elem->prev->next = elem->next;
+      }
+      if (elem->next) {
+        elem->next->prev = elem->prev;
+      }
+      if (elem == tail) {
+        tail = elem->prev;
+      }
+      elem->tracker_ptr->tracker_list_elem = nullptr;
+      delete elem;
+      --size;
+    }
+
+    absl::Time kth_time() const {
+      return kth_elem ? kth_elem->time : absl::InfiniteFuture();
     }
   };