diff --git a/lib/job_queue/job_queue.cpp b/lib/job_queue/job_queue.cpp
index 52403831d4..bbdad13f0c 100644
--- a/lib/job_queue/job_queue.cpp
+++ b/lib/job_queue/job_queue.cpp
@@ -886,7 +886,7 @@ static void handle_run_jobs(job_queue_type * queue, int num_total_run, bool verb
     potentially be quite high while running the DONE callback - should therefor not use
     too many threads.
   */
-  const int NUM_WORKER_THREADS = 4;
+  const int NUM_WORKER_THREADS = 1;
   queue->work_pool = thread_pool_alloc(NUM_WORKER_THREADS, true);
   res_log_debug("Allocated thread pool in job_queue_run_jobs");
 
diff --git a/python/res/job_queue/job_queue_manager.py b/python/res/job_queue/job_queue_manager.py
index 8b70ea35fb..e952bbd566 100644
--- a/python/res/job_queue/job_queue_manager.py
+++ b/python/res/job_queue/job_queue_manager.py
@@ -20,7 +20,7 @@
 from res.job_queue import JobStatusType
 from threading import BoundedSemaphore
 
-CONCURRENT_INTERNALIZATION = 10
+CONCURRENT_INTERNALIZATION = 1
 
 
 # TODO: there's no need for this class, all the behavior belongs in the queue