Cap 15 Managing Database Performance. Pedro F. Carvalho DBA Oracle

Transcrição

1 Cap 15 Managing Database Performance

2 Objectives After completing this lesson, you should be able to: Monitor the performance of sessions and services Use the SQL Tuning Advisor to: Identify SQL statements that are using the most resources Tune SQL statements that are using the most resources Use the SQL Access Advisor to tune a workload

3 Monitoramento de Performance Página inicial Gráficos mais detalhados

4 Monitoramento de Performance

5 Monitoramento de Performance

6 LAB Simular um Lock Abrir duas sessões (sys/hr) por um terminal no sqlplus Ambas realizar um update na tabela hr.department Observar o gráfico Kill em uma das sessões

7 Oracle Wait Events

8 Oracle Wait Events

9 Oracle Wait Events

10 Oracle Wait Events

11 Oracle Wait Events

12 -- banco lento consultar evets em espera SELECT gv$session_wait.seconds_in_wait tempo, gv$session.username usuario, gv$session.status status, gv$session_wait.sid sid, gv$session.serial#, gv$session_wait.event eventos, gv$session_wait.wait_class classe, gv$session.terminal, gv$session.machine, gv$session.module, gv$session.action FROM gv$session_wait, gv$session where gv$session_wait.sid = gv$session.sid(+) and STATUS = 'ACTIVE' and username is not null ORDER BY gv$session_wait.seconds_in_wait desc; Oracle Wait Events

13 Views de desempenho V$SYSSTAT statistic# name class value stat_id V$SYSTEM_WAIT_CLASS wait_class_id wait_class# wait_class total_waits time_waited V$SGASTAT pool name bytes V$EVENT_NAME event_number event_id name parameter1 parameter2 parameter3 wait_class V$SYSTEM_EVENT event total_waits total_timeouts time_waited average_wait time_waited_micro

14 Performance de sessão

15 Displaying Session-Related Statistics V$STATNAME statistic# name class V$SESSION_EVENT sid event total_waits total_timeouts time_waited average_wait max_wait time_waited_micro event_id V$SESSTAT sid statistic# value V$EVENT_NAME event# name parameter1 parameter2 parameter3 V$SESSION sid serial# username command osuser seq# event# event p1/2/3text p1/2/3 p1/2/3raw wait_class wait_time seconds_in_wait state...

16 Tuning Views Instance/Database V$DATABASE V$INSTANCE V$PARAMETER V$SPPARAMETER V$SYSTEM_PARAMETER V$PROCESS V$BGPROCESS V$PX_PROCESS_SYSSTAT V$SYSTEM_EVENT Memory V$BUFFER_POOL_STATISTICS V$LIBRARYCACHE V$SGAINFO V$PGASTAT Disk V$DATAFILE V$FILESTAT V$LOG V$LOG_HISTORY V$DBFILE V$TEMPFILE V$TEMPSEG_USAGE V$SEGMENT_STATISTICS Contention V$LOCK V$UNDOSTAT V$WAITSTAT V$LATCH

17 Automatic Workload Repository MMON ADDM finds top problems. SGA In-memory statistics SYSAUX 6:00 AM 7:00 AM 8:00 AM 9:00 AM Snapshot 1 Snapshot 2 Snapshot 3 Snapshot 4 9:30 AM

18 Relatório ASH

19 Relatório SNAPSHOT

20 SQL Tuning

21 Aonde identificar os Selects Lentos Ou por snapshot ou por ASH

22 Advisors SQL

23 Plano de Execução