From: Ian Jackson <ian@liberator.relativity.greenend.org.uk>
Date: Sun, 28 Jun 2009 15:06:45 +0000 (+0100)
Subject: adjust code from abandon.stability e19af2579b9619071d17d3fba67c2d0e3d225f61 to curren... 
X-Git-Tag: 1.9.2~90^2~11
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~yarrgweb/git?p=ypp-sc-tools.db-test.git;a=commitdiff_plain;h=c66cfd9d90974888907605f6d9888bcadd5fa433

adjust code from abandon.stability e19af2579b9619071d17d3fba67c2d0e3d225f61 to current context, ready for integration
---

diff --git a/pctb/pages.c b/pctb/pages.c
index 0081161..1a99701 100644
--- a/pctb/pages.c
+++ b/pctb/pages.c
@@ -321,6 +321,7 @@ static void wait_for_stability(Snapshot **output,
   va_start(al,fmt);
 
   Snapshot *last=0;
+  int nidentical=0;
   /* waits longer if we're going to return an image identical to previously
    * if previously==0, all images are considered identical to it */
 
@@ -333,33 +334,33 @@ static void wait_for_stability(Snapshot **output,
 	  last_input, previously, doing);
 
   for (;;) {
-    double at_snapshot= timestamp();
-    double need_sleep= min_update_allowance - (at_snapshot - last_input);
-    if (need_sleep > 0) { delay(need_sleep); continue; }
-
+    usleep(250000);
     snapshot(output);
 
-    if (!with_keypress &&
-	!(previously && identical(*output,previously))) {
-      debugf("PAGING  wait_for_stability  simple\n");
-      break;
-    }
-
-    if (last && identical(*output,last)) {
-      debugf("PAGING  wait_for_stability  stabilised\n");
-      break;
+    if (!last) {
+      debugf("PAGING  wait_for_stability first...\n");
+      last=*output; *output=0;
+    } else if (!identical(*output,last)) {
+      debugf("PAGING  wait_for_stability changed...\n");
+      free(last); last=*output; *output=0;
+      nidentical=0;
+    } else {
+      nidentical++;
+      int threshold=
+	!previously ? 3 :
+	identical(*output,previously) ? 3
+	: 1;
+      debugf("PAGING  wait_for_stability nidentical=%d threshold=%d\n",
+	      nidentical, threshold);
+      if (nidentical >= threshold)
+	break;
     }
-    
     progress_spinner("%s",doing);
 
-    debugf("PAGING  wait_for_stability  retry\n");
-
-    free_snapshot(&last); last=*output; *output=0;
-
     if (with_keypress)
       with_keypress();
 
-    delay(0.5);
+    usleep(250000);
   }
 
   free_snapshot(&last);