PGCon2008 - Final - we hope

PGCon 2008
The PostgreSQL Conference

Pavan Deolasee
Day Talks - first day (2008-05-22)
Room B
Start time 16:30
Duration 01:00
ID 105
Event type lecture
Track Hacker
Language en

HOT Inside

The Technical Architecture

This session will cover the technical architecture of HOT (Heap-Only-Tuples), a key feature of PostgreSQL 8.3.

Prior to HOT, frequent updates on a table would bloat the table and the indexes on it, negatively impacting long-term database performance. While frequent manual or automatic vacuuming could repair the table/index bloat, the same vacuuming caused performance problems by putting additional load on the database. HOT now attempts to address these problems by reclaiming the space used by the old, dead tuples without requiring vacuuming of the table.

Pavan will discuss the internals of HOT and the interesting technical challenges faced during HOT's development. He will also share HOT’s performance statistics and its limitations.