Avoid double lookup in pgstat_fetch_stat_tabentry()

[Drouvot, Bertrand]

Hi hackers,

Please find attached a patch proposal to avoid 2 calls to 
pgstat_fetch_stat_tabentry_ext() in pgstat_fetch_stat_tabentry() in case 
the relation is not a shared one and no statistics are found.

Thanks Andres for the suggestion done in [1].

[1]: 
https://www.postgresql.org/message-id/20221116201202.3k74ajawyom2c3eq%40awork3.anarazel.de

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.comdiff --git a/src/backend/utils/activity/pgstat_relation.c 
b/src/backend/utils/activity/pgstat_relation.c
index 55a355f583..a2a4fc6e2c 100644
--- a/src/backend/utils/activity/pgstat_relation.c
+++ b/src/backend/utils/activity/pgstat_relation.c
@@ -25,6 +25,7 @@
 #include "utils/pgstat_internal.h"
 #include "utils/rel.h"
 #include "utils/timestamp.h"
+#include "catalog/catalog.h"
 
 
 /* Record that's written to 2PC state file when pgstat state is persisted */
@@ -439,14 +440,8 @@ pgstat_fetch_stat_tabentry(Oid relid)
 {
        PgStat_StatTabEntry *tabentry;
 
-       tabentry = pgstat_fetch_stat_tabentry_ext(false, relid);
-       if (tabentry != NULL)
-               return tabentry;
+       tabentry = pgstat_fetch_stat_tabentry_ext(IsSharedRelation(relid), 
relid);
 
-       /*
-        * If we didn't find it, maybe it's a shared table.
-        */
-       tabentry = pgstat_fetch_stat_tabentry_ext(true, relid);
        return tabentry;
 }