In the stats test, delay for the stats collector to catch up using a

function that actually sleeps, instead of busy-waiting.  Perhaps this
will resolve some of the intermittent stats failures we keep seeing.

src/test/regress/expected/stats.out

@@ -24,17 +24,6 @@ SELECT t.seq_scan, t.seq_tup_read, t.idx_scan, t.idx_tup_fetch,
 -- enable statistics
 SET stats_block_level = on;
 SET stats_row_level = on;
--- helper function
-CREATE FUNCTION sleep(interval) RETURNS integer AS '
-DECLARE
-  endtime timestamp;
-BEGIN
-  endtime := timeofday()::timestamp + $1;
-  WHILE timeofday()::timestamp < endtime LOOP
-  END LOOP;
-  RETURN 0;
-END;
-' LANGUAGE 'plpgsql';
 -- do something
 SELECT count(*) FROM tenk2;
  count 
@@ -49,10 +38,10 @@ SELECT count(*) FROM tenk2 WHERE unique1 = 1;
 (1 row)
 
 -- let stats collector catch up
-SELECT sleep('0:0:2'::interval);
- sleep 
--------
-     0
+SELECT do_sleep(2);
+ do_sleep 
+----------
+ 
 (1 row)
 
 -- check effects
@@ -76,6 +65,4 @@ SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
  t        | t
 (1 row)
 
--- clean up
-DROP FUNCTION sleep(interval);
 -- End of Stats Test

src/test/regress/input/create_function_1.source

@@ -5,22 +5,22 @@
 CREATE FUNCTION widget_in(cstring)
    RETURNS widget
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 
 CREATE FUNCTION widget_out(widget)
    RETURNS cstring
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 
 CREATE FUNCTION int44in(cstring)
    RETURNS city_budget
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 
 CREATE FUNCTION int44out(city_budget)
    RETURNS cstring
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 
 CREATE FUNCTION check_primary_key ()
 	RETURNS trigger
@@ -50,7 +50,12 @@ CREATE FUNCTION ttdummy ()
 CREATE FUNCTION set_ttdummy (int4)
         RETURNS int4
         AS '@abs_builddir@/regress@DLSUFFIX@'
-        LANGUAGE 'C';
+        LANGUAGE 'C' STRICT;
+
+CREATE FUNCTION do_sleep (int4)
+        RETURNS void
+        AS '@abs_builddir@/regress@DLSUFFIX@'
+        LANGUAGE 'C' STRICT;
 
 -- Things that shouldn't work:
 

src/test/regress/output/create_function_1.source

@@ -4,24 +4,24 @@
 CREATE FUNCTION widget_in(cstring)
    RETURNS widget
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 NOTICE:  type "widget" is not yet defined
 DETAIL:  Creating a shell type definition.
 CREATE FUNCTION widget_out(widget)
    RETURNS cstring
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 NOTICE:  argument type widget is only a shell
 CREATE FUNCTION int44in(cstring)
    RETURNS city_budget
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 NOTICE:  type "city_budget" is not yet defined
 DETAIL:  Creating a shell type definition.
 CREATE FUNCTION int44out(city_budget)
    RETURNS cstring
    AS '@abs_builddir@/regress@DLSUFFIX@'
-   LANGUAGE 'c';
+   LANGUAGE 'C' STRICT;
 NOTICE:  argument type city_budget is only a shell
 CREATE FUNCTION check_primary_key ()
 	RETURNS trigger
@@ -46,7 +46,11 @@ CREATE FUNCTION ttdummy ()
 CREATE FUNCTION set_ttdummy (int4)
         RETURNS int4
         AS '@abs_builddir@/regress@DLSUFFIX@'
-        LANGUAGE 'C';
+        LANGUAGE 'C' STRICT;
+CREATE FUNCTION do_sleep (int4)
+        RETURNS void
+        AS '@abs_builddir@/regress@DLSUFFIX@'
+        LANGUAGE 'C' STRICT;
 -- Things that shouldn't work:
 CREATE FUNCTION test1 (int) RETURNS int LANGUAGE sql
     AS 'SELECT ''not an integer'';';

src/test/regress/regress.c

 /*
- * $PostgreSQL: pgsql/src/test/regress/regress.c,v 1.62 2004/10/21 19:28:36 tgl Exp $
+ * $PostgreSQL: pgsql/src/test/regress/regress.c,v 1.63 2005/07/23 14:18:56 tgl Exp $
  */
 
 #include "postgres.h"
@@ -26,6 +26,8 @@ extern char *reverse_name(char *string);
 extern int	oldstyle_length(int n, text *t);
 extern Datum int44in(PG_FUNCTION_ARGS);
 extern Datum int44out(PG_FUNCTION_ARGS);
+extern Datum do_sleep(PG_FUNCTION_ARGS);
+
 
 /*
  * Distance from a point to a path
@@ -733,3 +735,18 @@ int44out(PG_FUNCTION_ARGS)
 	*--walk = '\0';
 	PG_RETURN_CSTRING(result);
 }
+
+/*
+ * do_sleep - delay for N seconds
+ */
+PG_FUNCTION_INFO_V1(do_sleep);
+
+Datum
+do_sleep(PG_FUNCTION_ARGS)
+{
+	int32		secs = PG_GETARG_INT32(0);
+
+	pg_usleep(secs * 1000000L);
+
+	PG_RETURN_VOID();
+}

src/test/regress/sql/stats.sql

@@ -24,24 +24,12 @@ SELECT t.seq_scan, t.seq_tup_read, t.idx_scan, t.idx_tup_fetch,
 SET stats_block_level = on;
 SET stats_row_level = on;
 
--- helper function
-CREATE FUNCTION sleep(interval) RETURNS integer AS '
-DECLARE
-  endtime timestamp;
-BEGIN
-  endtime := timeofday()::timestamp + $1;
-  WHILE timeofday()::timestamp < endtime LOOP
-  END LOOP;
-  RETURN 0;
-END;
-' LANGUAGE 'plpgsql';
-
 -- do something
 SELECT count(*) FROM tenk2;
 SELECT count(*) FROM tenk2 WHERE unique1 = 1;
 
 -- let stats collector catch up
-SELECT sleep('0:0:2'::interval);
+SELECT do_sleep(2);
 
 -- check effects
 SELECT st.seq_scan >= pr.seq_scan + 1,
@@ -55,7 +43,4 @@ SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
   FROM pg_statio_user_tables AS st, pg_class AS cl, prevstats AS pr
  WHERE st.relname='tenk2' AND cl.relname='tenk2';
 
--- clean up
-DROP FUNCTION sleep(interval);
-
 -- End of Stats Test