Database Reference
In-Depth Information
Mast
Inst RESOURCE_NAME node VALUE_BLK
---- ------------------------------ ---- -----------------------------------------
2 [0xb6e64b][0x0],[SV][ext 0x0,0 2 0x
82c10b
00000000000000000000000000 .
Oracle Database uses special representation to store the numbers, apparently for cross-platform compatibility
reasons. For example, a value of 10 is represented as a two-byte value. The following two SQL statements can be used
to identify the internal representation:
SQL> select dump(10) from dual;
DUMP(10)
-------------------
Typ=2 Len=2: 193,11
Converting the values 193 and 11, we get c10b:
select to_char(193,'xx')||to_char(11,'xx') from dual;
TO_CHA
------
c1 b
RAC background processes coordinate the value_blk column value and return the next value to the foreground
process. As expected, locks are also acquired by the background processes on the SV resource. In the following output,
PID 24313 has
KJUSERNL
mode lock, and PID 24313 is LCK0 process.
REM Identify all GES locks for that resource.
col state format a10
col inst_id format 99 head Inst
col owner_node format 99 head 'Owner|Node'
SQL> SELECT inst_id, resource_name1, pid, state, owner_node , grant_level, request_level
FROM gv$ges_enqueue WHERE resource_name1 LIKE '&resource_name%'
/
Owner
Inst RESOURCE_NAME1 PID STATE Node GRANT_LEV REQUEST_L
---- ------------------------------ ---------- ---------- ----- --------- ---------
2 [0xb6e64b][0x0],[SV][ext 0x0,0 24313 GRANTED 1 KJUSERNL KJUSERNL
3 [0xb6e64b][0x0],[SV][ext 0x0,0 4416 GRANTED 2 KJUSERNL KJUSERNL
3 [0xb6e64b][0x0],[SV][ext 0x0,0 0 GRANTED 1 KJUSEREX KJUSEREX
Let us understand how to identify the object_id associated with DFS lock handle wait event and SV resource
type. The first line shows the DFS lock handle wait event. Column id1 in that trace file line shows the object_id of the
sequence involved in DFS lock handle contention. Note that the
obj#
field value from the trace line is not referring to
the sequence (as of release 11.2).
nam='DFS lock handle' ela= 827 type|mode=1398145029 id1=
11986507
id2=0 obj#=-1
col object_name format a30
