何查看session執行的sql語句老生常談:首先要用到上面的四個動態視圖。實驗:Connected to:Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - ProductionWith the Partitioning, OLAP and Data Mining optionsSQL> insert into jiajie values(99);1 row created.SQL> show userUSER
Using the Large Pool使用large PoolUnlike the shared pool, the large pool does not have an LRU list. Oracle does notattempt to age objects out of the large pool.不像shared pool,large pool不含有LRU 列表。ORACLE 不會嘗試把對象因長期不用而從large pool中去除.You should consider
Past ImagesRecall that a past image is a copy of the block, including any changes, that is retained by the sendinginstance when a block is transferred to another instance.過去鏡像是某塊的一個複製,包含所有的改動,當資料區塊傳輸到別的執行個體上的時候,它會被發送執行個體儲存。Past images are only
System Change Numbers (SCNs)In order to track changes to data blocks, Oracle assigns a numeric identifier to each version of the block.This identifier is effectively a logical time stamp and is known as an SCN. Oracle records the SCN in the redo
Optimizing the Global CacheIn this section, you have seen that the amount of work performed by the cluster in support of theGlobal Cache Service is highly dependent on the usage of data blocks within the
Configuring and Using the Redo Log Buffer配置和使用redo log bufferServer processes making changes to data blocks in the buffer cache generate redo datainto the log buffer. LGWR begins writing to copy entries from the redo log buffer tothe online redo log
一般來說,AIX 作業系統針對ORACLE資料庫的最佳化並不複雜,主要集中在非同步I/O,虛擬記憶體管理等方面。對於非同步I/O,首先要明白一點,針對裸裝置和針對檔案系統的最佳化是不同的。AIX 5L對於裸裝置使用非同步I/O是核心支援的,因此不需要使用AIO Server;而檔案系統使用非同步I/O時,則需要使用AIO Server。通過以下命令可以檢查非同步I/O的設定:LN-BILL-DB-JF|| /#lsattr -El aioautoconfig available STATE
Shared Pool: Dictionary Cache Statisticsshared pool:字典記憶體統計資訊Typically, if the shared pool is adequately sized for the library cache, it will also beadequate for the dictionary cache data.標準情況下,如果共用池的大小對於library cache 的大小是充足的,它對於Librarycache
segment header If the contention is on the segment header, then this is most likely freelist contention.如果壓力存在於segment的頭部,那麼這最可能是free list壓力。 Automatic segment-space management in locally managed tablespaces eliminates theneed to specify the PCTUSED,