Index: articlelist.c
===================================================================
RCS file: /cvs/gnome/pan/pan/articlelist.c,v
retrieving revision 1.602
diff -u -r1.602 articlelist.c
--- articlelist.c	3 Feb 2003 20:58:02 -0000	1.602
+++ articlelist.c	4 Feb 2003 08:54:21 -0000
@@ -1230,10 +1230,30 @@
 		pan_unlock ();
 		g_static_mutex_unlock (&article_ctree_lock);
 
-		/* remove them from our array */
-		for (i=0; i<articles->len; ++i) {
-			const Article * needle = ARTICLE(g_ptr_array_index(articles,i));
-			g_ptr_array_remove (my_articles, (gpointer)needle);
+		/* remove them from our array.
+		 * for small numbers g_ptr_array_remove() is okay, but for huge groups we're
+		 * better off just rebuilding my_articles than to memmove
+		 * 50000 pointers 30000 times. */
+		if (articles->len < 5) {
+			/* low overhead, good if user just hit 'delete' key on an article */
+			for (i=0; i<articles->len; ++i)
+				g_ptr_array_remove (my_articles, g_ptr_array_index (articles, i));
+		} else {
+			/* more overhead, but scales better */
+			GHashTable * del_hash = g_hash_table_new (g_str_hash, g_str_equal);
+			GPtrArray * tmp = g_ptr_array_sized_new (my_articles->len);
+			for (i=0; i<articles->len; ++i) {
+				Article * a = ARTICLE (g_ptr_array_index (articles, i));
+				g_hash_table_insert (del_hash, (gpointer)article_get_message_id(a), a);
+			}
+			for (i=0; i<my_articles->len; ++i) {
+				Article * a = ARTICLE (g_ptr_array_index (my_articles, i));
+				if (g_hash_table_lookup (del_hash, article_get_message_id (a)) == NULL)
+					g_ptr_array_add (tmp, a);
+			}
+			pan_g_ptr_array_assign (my_articles, tmp->pdata, tmp->len);
+			g_ptr_array_free (tmp, TRUE);
+			g_hash_table_destroy (del_hash);
 		}
 	}