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This article introduces you how to understand Oracle 11g architecture, the content is very detailed, interested partners can refer to it, I hope it can help you.

Oracle 11g architecture:

Oracle operating principle:

Efficient processing of data

Memory mechanism:

Core memory 3 major components:

Shared Pool

Database Buffer Cache

Redo Log Buffer

Shared Pool:

Improve the efficiency of SQL statements in the parsing phase.

Data Dictionary Cache Data dictionary cache improves semantic parsing efficiency during SQL statement parsing.

Get all the data dictionary information into memory, and you won't need to read the disk next time. High efficiency.

The generated execution plan is placed in the Library Cache, so there is no need to generate an execution plan next time. Direct soft parsing. Improve analytical efficiency.

Database Buffer Cache：

A database cache exists to improve the efficiency of SQL statements at the execution stage.

Redo Log Buffer：

Query statements generally do not generate redo.

Large query statements do not generate redo except in the special case of delayed block cleanup.

Add, delete and modify, DML operations, in order to ensure ACID characteristics. Make data resilient. Each modification action records information about data variability.

A large amount of log information is recorded every hour and every second. If each of these log messages were written to disk, disk overhead pressure would be significant.

In order to relieve the pressure of disk write redo, we introduce the efficient redo log buffer component to improve the log writing efficiency.

Do disk writers prefer sequential or random writing? I like to write in order.

Disks are good at sequential and random writes, so introduce raid0 and ASM.

Therefore, it is necessary to accumulate certain data and write it again to improve the writing efficiency. Redo Log Buffer is introduced.

Database efficiency is achieved through instance instances of oracle and through memory structure components of instance.

Processing data in a database is accomplished through various process components in an instance of oracle.

PMON: Specialized in cleaning up abnormal processes

SMON: Specially handles instance recovery after instance suspension

DBWR: database writer that handles dirty data and writes it to a data file

LGWR: Log Writer written in a log information set

CKPT: CheckPoint CKPT processes that have unified data files, control files, and log files to maintain consistency. Each process is doing something in an independent direction.

The database efficiently processes data stored in data files, where data files exist, where log files exist is determined by the control file.

The data portion of efficiently processed data consists of a variety of files. Data is stored in data files, and the location of data files and log files is specified by control files.

Efficient processing of the data part of the data is achieved through the various core files of the database. Efficient processing of data

instance Efficient processing memory + processes

data database

Data hanging: data file, control file, log file which of these three files hanging.

The database is suspended. It should be said that the database instance is suspended.

About how to understand Oracle 11g architecture to share here, I hope the above content can be of some help to everyone, you can learn more knowledge. If you think the article is good, you can share it so that more people can see it.

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