Eventos Oracle Wait que todos deveriam saber

select event from V$session_wait where sid=&1

select * from dba_waiters

• fazendo um backup dos arquivos de controle
• compartilhando informações (entre instâncias) do controlfile
• lendo outros blocos dos arquivos de controle
• lendo o bloco de cabeçalho

Select event, total_waits, total_timeouts, time_waited, average_wait
from v$system_event
where event = 'log buffer space';
Select sid, event, seconds_in_wait, state
from v$session_wait
where event = 'log buffer space';
Select name, value
from v$sysstat
where name in ('redo log space requests');

Select v1.value as redo_buff_alloc_retries, v2.value as redo_entries,
trunc(v1.value/v2.value,4) as pct_buff_alloc_retries
from v$sysstat v1, v$sysstat v2
where v1.name = 'redo buffer allocation retries'
and v2.name = 'redo entries';

SELECT
addr,
sleeps
FROM
v$latch_children c,
v$latchname n
WHERE
n.name='cache buffers chains' and
c.latch#=n.latch# and
sleeps > 100
ORDER BY sleeps
/

SELECT file#, dbablk, class, state, TCH
FROM X$BH
WHERE HLADDR='address of latch';

desc v$session_wait

Name Null? Type
--------------------------- -------- ------------
SID NUMBER
SEQ# NUMBER
EVENT VARCHAR2(64)
P1TEXT VARCHAR2(64)
P1 NUMBER
P1RAW RAW(4)
P2TEXT VARCHAR2(64)
P2 NUMBER
P2RAW RAW(4)
P3TEXT VARCHAR2(64)
P3 NUMBER
P3RAW RAW(4)
WAIT_CLASS_ID NUMBER
WAIT_CLASS# NUMBER
WAIT_CLASS VARCHAR2(64)
WAIT_TIME NUMBER
SECONDS_IN_WAIT NUMBER
STATE VARCHAR2(19)

The meaning of each wait event corresponds know by querying the V$EVENT_NAME p1, p2, p3 of
col name format a25;
col p1 format a10;
col p2 format a10;
col p3 format a10;
SELECT NAME, PARAMETER1 P1, PARAMETER2 P2, PARAMETER3 P3
FROM V$EVENT_NAME
WHERE NAME = '&event_name';

select username, event, p1, p2 from  v$session_wait  where sid = 4563;

USERNAME    EVENT            SID P1 P2
---------- ----------------- --- -- ---
APPS         buffer busy waits 4563  11  545

SQL> select segment_name,segment_type
from dba_extents
where file_id = 11
and 45 between block_id and block_id + blocks – 1;