debian: use uwsgi cheaper subsystem for workers (#51313)

debian/uwsgi.ini

@@ -1,18 +1,35 @@
 [uwsgi]
 auto-procname = true
 procname-prefix-spaced = combo
+strict = true
 
 plugin = python3
+single-interpreter = true
 module = combo.wsgi:application
+need-app = true
 
 http-socket = /run/combo/combo.sock
 chmod-socket = 666
 vacuum = true
 
 master = true
-processes = 5
-harakiri = 120
 enable-threads = true
+harakiri = 120
+
+processes = 500
+
+plugin = cheaper_busyness
+cheaper-algo = busyness
+cheaper = 5
+cheaper-initial = 10
+cheaper-overload = 5
+cheaper-step = 10
+cheaper-busyness-multiplier = 30
+cheaper-busyness-min = 20
+cheaper-busyness-max = 70
+cheaper-busyness-backlog-alert = 16
+cheaper-busyness-backlog-step = 2
+
 max-requests = 500
 max-worker-lifetime = 7200