From 7b17cfd8056e627abcb270056671e9c862cb193d Mon Sep 17 00:00:00 2001
From: Lars Holmberg <Lars.Holmberg@svenskaspel.se>
Date: Fri, 3 May 2024 18:06:04 +0200
Subject: [PATCH 1/2] Use deque for tasks in TaskSet instead of plain list

---
 locust/user/task.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/locust/user/task.py b/locust/user/task.py
index 1b40c7b11c..11089b9772 100644
--- a/locust/user/task.py
+++ b/locust/user/task.py
@@ -5,6 +5,7 @@
 import logging
 import random
 import traceback
+from collections import deque
 from time import time
 from typing import (
     TYPE_CHECKING,
@@ -276,7 +277,7 @@ class ForumPage(TaskSet):
     _parent: User
 
     def __init__(self, parent: User) -> None:
-        self._task_queue: list[Callable] = []
+        self._task_queue: deque = deque()
         self._time_start = time()
 
         if isinstance(parent, TaskSet):
@@ -369,7 +370,7 @@ def run(self):
                     raise
 
     def execute_next_task(self):
-        self.execute_task(self._task_queue.pop(0))
+        self.execute_task(self._task_queue.popleft())
 
     def execute_task(self, task):
         # check if the function is a method bound to the current locust, and if so, don't pass self as first argument
@@ -391,7 +392,7 @@ def schedule_task(self, task_callable, first=False):
         :param first: Optional keyword argument. If True, the task will be put first in the queue.
         """
         if first:
-            self._task_queue.insert(0, task_callable)
+            self._task_queue.appendleft(task_callable)
         else:
             self._task_queue.append(task_callable)
 

From 8ede95b290b5842ce1133cd31d104582d5afe846 Mon Sep 17 00:00:00 2001
From: Lars Holmberg <Lars.Holmberg@svenskaspel.se>
Date: Fri, 3 May 2024 18:08:07 +0200
Subject: [PATCH 2/2] Adjust test case to use deque too

---
 locust/test/test_runners.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/locust/test/test_runners.py b/locust/test/test_runners.py
index a903b2733a..0397e02550 100644
--- a/locust/test/test_runners.py
+++ b/locust/test/test_runners.py
@@ -35,7 +35,7 @@
 import random
 import time
 import unittest
-from collections import defaultdict
+from collections import defaultdict, deque
 from operator import itemgetter
 from unittest import mock
 
@@ -2984,7 +2984,7 @@ def test_exception_is_caught(self):
         class MyTaskSet(TaskSet):
             def __init__(self, *a, **kw):
                 super().__init__(*a, **kw)
-                self._task_queue = [self.will_error, self.will_stop]
+                self._task_queue = deque([self.will_error, self.will_stop])
 
             @task(1)
             def will_error(self):