Reconstruction of Library cache pin and procedure

As mentioned earlier, the processing of the ORACLE10G reconstruction procedure has increased, and when I first saw this enhancement, I wondered if this enhancement would reduce the already-troubled library cache competition.

Let's take a look at the following tests, first performing the action in the first session:

SQL> create or replace PROCEDURE pining
2 IS
3 BEGIN
4 NULL;
5 END;
6 /

Procedure created.

SQL>
SQL> alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss';

Session altered.

SQL> create or replace procedure calling
2 is
3 begin
4 pining;
5 dbms_lock.sleep(60);
6 end;
7 /

Procedure created.

SQL>
SQL> col object_name for a30
SQL> select object_name,last_ddl_time from dba_objects where object_name in ('PINING','CALLING');

OBJECT_NAME LAST_DDL_TIME
------------------------------ -------------------
CALLING 2007-04-02 09:12:57
PINING 2007-04-02 09:12:57

SQL>
SQL> exec calling;

At this point calling's reference to pining will get a shared pin on the body of pining, at which time a rebuild procedure operation is performed on another session:

SQL> create or replace PROCEDURE pining
2 IS
3 BEGIN
4 NULL;
5 END;
6 /