PostgreSQL Internals

Cache Buffer Chains (CBC) is a mechanism used by the PostgreSQL storage engine to manage the buffer cache and minimize the amount of disk I/O. The buffer cache is a region of memory that is […]

PgBouncer is a lightweight connection pooler for PostgreSQL. It is used to reduce the overhead of establishing a new connection to a PostgreSQL database for each client request. By pooling connections, PgBouncer can handle a […]

The source code for the PostgreSQL LALR(1) parser is written in C and can be found in the PostgreSQL source code repository. The main components of the parser are: To understand how the parser works, […]

The freelists in PostgreSQL are implemented as a linked list of pages. Each page is a unit of disk space that is managed by the freelist, and its size is determined by the block size […]

The CPU Cache Buffers Chains Latch in PostgreSQL is a synchronization mechanism that protects the buffer cache data structure. The buffer cache is a pool of memory used by PostgreSQL to cache disk blocks that […]

A reverse key index in PostgreSQL is an index that stores its keys in reverse order. This type of index can help improve query performance when the order of the keys in a table’s primary […]

Mutexes (short for mutual exclusion) are used in PostgreSQL to ensure that only one thread of execution can access a shared resource at any given time. Here are some tips and techniques for working with […]

In PostgreSQL, row locks are used to control access to individual rows in a table, allowing multiple transactions to access the same table without interfering with each other. Row level locking is a mechanism that […]

Parallel Hash Joins in PostgreSQL are a type of join operation that can be executed in parallel, allowing for faster and more efficient execution of database queries. In a hash join, the database first builds […]

In PostgreSQL, Direct Path Read is implemented as an optimization technique for full table scans, which aims to bypass the buffer cache and read data directly from disk into the process memory, reducing the overhead […]