search
HomeDatabaseOracleoracle memory modification

Oracle memory modification

Oracle is the current leader in enterprise-level database systems. Despite this, some users always encounter some memory limit issues. Oracle can either use shared memory or files in the operating system's file system, but either way, memory limitations may affect Oracle's performance, and we will need to make some adjustments and memory modifications for this issue.

Why is there a memory limit?

Oracle will pre-allocate a piece of memory as the main storage area when it starts, so the initial amount of memory for the program is determined. During operation, Oracle may automatically increase memory, such as the size of automatic shared memory, but you need to carefully check whether the memory size exceeds the physical memory size limit. If the limit is exceeded, the operating system will forcefully terminate Oracle execution.

How to adjust shared memory?

Shared memory is implemented at the operating system level. The operating system reserves a memory block as shared memory and grants Oracle user permissions to use the memory block. In order to adjust the shared memory, we can follow the steps below:

  1. View the size of the shared memory in the system

Check the manual of the operating system and Oracle version you are using to find out How to view allocated shared memory. Taking Linux as an example, use the "ipcs -m" command to check the size of the shared memory.

  1. Change the shared memory size

Many parameters of the operating system can be adjusted while maintaining at least one of the same extreme values ​​in the minimum list of each process. On the Oracle system side, there are two parameters that can be used to change the size of shared memory: SGA and PGA.

  • SGA (System Global Area), used to allocate Oracle's memory in shared memory. This can be tuned using Oracle's SGA utility.
  • PGA (Program Global Area) is used to allocate a certain amount of memory to each process. You can set PGA_LIMIT in the startup options to change the size, or you can use PGA_AGGREGATE_TARGET to let Oracle adjust the size automatically.

You need to modify these parameters carefully to avoid affecting the overall stability of the system.

How to adjust the file memory in the operating system file system?

File memory in the operating system file system also affects Oracle performance. They are called Shared Memory Files and are usually created by the operating system to store shared memory. The following are some common files:

  • /dev/shm: A temporary file system used to create shared memory files under Linux.
  • /tmp: Used to store shared memory files in many Linux installations.
  • /var/tmp: Another directory used to store shared memory files.

Before adjusting the memory file size, you need to determine the currently used file directory and obtain permissions. You can use the following command to view the currently used directory and its size:

df -h /dev/shm

Next, you can try to adjust some parameters of using the directory, such as inode, Quantity and size. You can modify these parameters using the mount command, or change the parameters of the operating system itself. If you're not sure how to adjust these parameters, check your operating system's official documentation.

Conclusion

Oracle is a very powerful enterprise-level database system. Despite this, some users still experience some memory limit issues. We can help Oracle overcome these limitations by tuning shared memory and file memory in the operating system file system. However, before making any changes, be sure to consult the official documentation in order to properly understand and modify the parameters of the database and operating system.

The above is the detailed content of oracle memory modification. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
What are the commonly used segments in oracle databasesWhat are the commonly used segments in oracle databasesMar 04, 2025 pm 06:08 PM

This article examines Oracle database segment types (data, index, rollback, temporary), their performance implications, and management. It emphasizes choosing appropriate segment types based on workload and data characteristics for optimal efficienc

How do I use cursors in PL/SQL to process multiple rows of data?How do I use cursors in PL/SQL to process multiple rows of data?Mar 13, 2025 pm 01:16 PM

This article explains PL/SQL cursors for row-by-row data processing. It details cursor declaration, opening, fetching, and closing, comparing implicit, explicit, and ref cursors. Techniques for efficient large dataset handling and using FOR loops

What are the oracle database installation client tools?What are the oracle database installation client tools?Mar 04, 2025 pm 06:09 PM

This article explores Oracle Database client tools, essential for interacting with Oracle databases without a full server installation. It details commonly used tools like SQL*Plus, SQL Developer, Enterprise Manager, and RMAN, highlighting their fun

What default tablespaces does the oracle database provide?What default tablespaces does the oracle database provide?Mar 04, 2025 pm 06:10 PM

This article examines Oracle's default tablespaces (SYSTEM, SYSAUX, USERS), their characteristics, identification methods, and performance implications. It argues against relying on defaults, emphasizing the importance of creating separate tablespac

What are the performance testing tools for oracle databasesWhat are the performance testing tools for oracle databasesMar 04, 2025 pm 06:11 PM

This article explores Oracle database performance testing tools. It discusses selecting the right tool based on budget, complexity, and features like monitoring, diagnostics, workload simulation, and reporting. The article also details effective bo

How to download oracle databaseHow to download oracle databaseMar 04, 2025 pm 06:07 PM

This article guides users through downloading Oracle Database. It details the process, emphasizing edition selection (Express, Standard, Enterprise), platform compatibility, and license agreement acceptance. System requirements and edition suitabil

How do I use Oracle Data Masking and Subsetting to protect sensitive data?How do I use Oracle Data Masking and Subsetting to protect sensitive data?Mar 13, 2025 pm 01:19 PM

This article details Oracle Data Masking and Subsetting (DMS), a solution for protecting sensitive data. It covers identifying sensitive data, defining masking rules (shuffling, substitution, randomization), setting up jobs, monitoring, and deployme

How do I create users and roles in Oracle?How do I create users and roles in Oracle?Mar 17, 2025 pm 06:41 PM

The article explains how to create users and roles in Oracle using SQL commands, and discusses best practices for managing user permissions, including using roles, following the principle of least privilege, and regular audits.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

Repo: How To Revive Teammates
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Atom editor mac version download

Atom editor mac version download

The most popular open source editor

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

SublimeText3 Linux new version

SublimeText3 Linux new version

SublimeText3 Linux latest version

VSCode Windows 64-bit Download

VSCode Windows 64-bit Download

A free and powerful IDE editor launched by Microsoft

ZendStudio 13.5.1 Mac

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment