Introduction to Oracle Memory Structures (69)

Oracle uses memory to store information such as the following:
■ Program code
■ Information about a connected session, even if it is not currently active
■ Information needed during program execution (for example, the current state of a
query from which rows are being fetched)
■ Information that is shared and communicated among Oracle processes (for
example, locking information)
■ Cached data that is also permanently stored on peripheral memory (for example,
data blocks and redo log entries)
The basic memory structures associated with Oracle include:
■ System Global Area (SGA), which is shared by all server and background
processes.
■ Program Global Areas (PGA), which is private to each server and background
process; there is one PGA for each process.

Oracle記憶體儲存以下資訊 :
1. 程式程式碼
2. 已連線會話資訊
3. 程式執行需要的資訊
4. Oracle程式間共享 ， 通訊的資訊
快取資料
基本的記憶體結構 ：
1. sga ， 所有的服務和後臺程式共享
2. pga ， 對於每個服務和後臺進行是私有的

[@more@]