When reloading postgresql.conf, log what parameters actually changed

diff --git a/src/backend/utils/misc/guc-file.l b/src/backend/utils/misc/guc-file.l
index 9e9c3f7793950ce1503f731ef4459b04b9fe61ea..b1ff03666a9b9232cf6f914d5c01cebdd080f1a5 100644 (file)
--- a/src/backend/utils/misc/guc-file.l
+++ b/src/backend/utils/misc/guc-file.l
@@ -283,6 +283,10 @@ ProcessConfigFile(GucContext context)
                /* Now we can re-apply the wired-in default */
                set_config_option(gconf->name, NULL, context, PGC_S_DEFAULT,
                                                  GUC_ACTION_SET, true);
+               if (context == PGC_SIGHUP)
+                       ereport(elevel,
+                                       (errmsg("parameter \"%s\" removed from configuration file, reset to default",
+                                                       gconf->name)));
        }
 
        /*
@@ -309,9 +313,18 @@ ProcessConfigFile(GucContext context)
        /* If we got here all the options checked out okay, so apply them. */
        for (item = head; item; item = item->next)
        {
+               char *pre_value = NULL;
+
+               if (context == PGC_SIGHUP)
+                       pre_value = pstrdup(GetConfigOption(item->name));
+
                if (set_config_option(item->name, item->value, context,
                                                                 PGC_S_FILE, GUC_ACTION_SET, true))
                {
+                       if (pre_value && strcmp(pre_value, GetConfigOption(item->name)) != 0)
+                               ereport(elevel,
+                                               (errmsg("parameter \"%s\" changed to \"%s\"",
+                                                               item->name, item->value)));
                        set_config_sourcefile(item->name, item->filename,
                                                                  item->sourceline);
                }