5.3 状態診断でのCluster Health Advisorの使用
Oracle Cluster Health Advisorは問題を自律的に収集して解決し、グリッド・インフラストラクチャ管理リポジトリ(GIMR)に履歴を格納します。
Oracle Grid InfrastructureユーザーはCHACTLを使用して、格納されている情報を問い合せることができます。
診断データを問い合せるには:
例5-1 テキストおよびHTML形式のCluster Health Advisorの出力例
次の例は、
oltpacbdという名前のデータベースに対するchactl query diagnosisコマンドのデフォルトのテキスト出力を示しています。$ chactl query diagnosis -db oltpacdb -start "2016-02-01 02:52:50" -end "2016-02-01 03:19:15"
2016-02-01 01:47:10.0 Database oltpacdb DB Control File IO Performance (oltpacdb_1) [detected]
2016-02-01 01:47:10.0 Database oltpacdb DB Control File IO Performance (oltpacdb_2) [detected]
2016-02-01 02:52:15.0 Database oltpacdb DB CPU Utilization (oltpacdb_2) [detected]
2016-02-01 02:52:50.0 Database oltpacdb DB CPU Utilization (oltpacdb_1) [detected]
2016-02-01 02:59:35.0 Database oltpacdb DB Log File Switch (oltpacdb_1) [detected]
2016-02-01 02:59:45.0 Database oltpacdb DB Log File Switch (oltpacdb_2) [detected]
Problem: DB Control File IO Performance
Description: CHA has detected that reads or writes to the control files are slower than expected.
Cause: The Cluster Health Advisor (CHA) detected that reads or writes to the control files were slow
because of an increase in disk IO.
The slow control file reads and writes may have an impact on checkpoint and Log Writer (LGWR) performance.
Action: Separate the control files from other database files and move them to faster disks or Solid State Devices.
Problem: DB CPU Utilization
Description: CHA detected larger than expected CPU utilization for this database.
Cause: The Cluster Health Advisor (CHA) detected an increase in database CPU utilization
because of an increase in the database workload.
Action: Identify the CPU intensive queries by using the Automatic Diagnostic and Defect Manager (ADDM) and
follow the recommendations given there. Limit the number of CPU intensive queries or
relocate sessions to less busy machines. Add CPUs if the CPU capacity is insufficent to support
the load without a performance degradation or effects on other databases.
Problem: DB Log File Switch
Description: CHA detected that database sessions are waiting longer than expected for log switch completions.
Cause: The Cluster Health Advisor (CHA) detected high contention during log switches
because the redo log files were small and the redo logs switched frequently.
Action: Increase the size of the redo logs.
タイムスタンプには、特定のホストまたはデータベースで問題が検出された日時が表示されます。
注意:
同じ問題が異なるホストや異なる時刻に発生することがありますが、診断には、問題およびその潜在的な影響のすべての詳細が表示されます。問題ごとに、対象を絞った修正または予防処理も表示されます。
次に、HTML形式の出力の例を示します。
$ chactl query diagnosis -start "2016-07-03 20:50:00" -end "2016-07-04 03:50:00" -htmlfile ~/chaprob.html