commit 3322055b392f20f4b97122a8034e479719e4b86d
author Paul Jakma <paul@quagga.net> Mon Jan 11 13:55:01 2010 +0000
committer Paul Jakma <paul@quagga.net> Wed Dec 08 16:53:09 2010 +0000
tree eacb5bc1e5b5864241e0864b5f78e233e7b828c0
parent e276eb82820eb92d221f183496e28da4ffe0fe68

lib: Make workqueue more conservative about ramping up

* workqueue.c: (work_queue_run) Err more on the side of keeping granularity
  down, by being more conservative about increasing it.
  Also, fix mispelling.

lib/workqueue.c

diff --git a/lib/workqueue.c b/lib/workqueue.c
index 7c811ed..52b5f41 100644
--- a/lib/workqueue.c
+++ b/lib/workqueue.c
@@ -341,7 +341,7 @@
 
 stats:
 
-#define WQ_HYSTERIS_FACTOR 2
+#define WQ_HYSTERESIS_FACTOR 4
 
   /* we yielded, check whether granularity should be reduced */
   if (yielded && (cycles < wq->cycles.granularity))
@@ -349,17 +349,18 @@
       wq->cycles.granularity = ((cycles > 0) ? cycles 
                                              : WORK_QUEUE_MIN_GRANULARITY);
     }
-  
-  if (cycles >= (wq->cycles.granularity))
+  /* otherwise, should granularity increase? */
+  else if (cycles >= (wq->cycles.granularity))
     {
       if (cycles > wq->cycles.best)
         wq->cycles.best = cycles;
       
-      /* along with yielded check, provides hysteris for granularity */
-      if (cycles > (wq->cycles.granularity * WQ_HYSTERIS_FACTOR * 2))
-        wq->cycles.granularity *= WQ_HYSTERIS_FACTOR; /* quick ramp-up */
-      else if (cycles > (wq->cycles.granularity * WQ_HYSTERIS_FACTOR))
-        wq->cycles.granularity += WQ_HYSTERIS_FACTOR;
+      /* along with yielded check, provides hysteresis for granularity */
+      if (cycles > (wq->cycles.granularity * WQ_HYSTERESIS_FACTOR
+                                           * WQ_HYSTERESIS_FACTOR))
+        wq->cycles.granularity *= WQ_HYSTERESIS_FACTOR; /* quick ramp-up */
+      else if (cycles > (wq->cycles.granularity * WQ_HYSTERESIS_FACTOR))
+        wq->cycles.granularity += WQ_HYSTERESIS_FACTOR;
     }
 #undef WQ_HYSTERIS_FACTOR