pgcompacttable is a tool for reducing size of bloated tables and indexes without heavy locks.
It is designed to reorganize data in tables and rebuild indexes in order to revert back disk space without database performance impact.
pgcompacttable
is written in Perl and requires Perl DBI library, obviously with PostgreSQL support module. Dependencies can be easy installed:
apt-get install libdbi-perl libdbd-pg-perl
yum install perl-Time-HiRes perl-DBI perl-DBD-Pg
In target database contrib module pgstattuple
should be installed via create extension if not exists pgstattuple;
pgcompacttable
can be run from any OS user (and even on another host, see --host
option; although it is recommended to run it on same host with target database), but PostgreSQL Superuser access is required. Preferred way is to run as PostgreSQL cluster owner, usually postgres
. In this case pgcompacttable
can perform ionice -c 3
for PostgreSQL backend pid to lower IO priority.
pgcompacttable --man
Prints list of available options and usage information.
pgcompacttable --all --verbose
Compacts all bloated tables in all databases in the cluster, including indexes. Prints additional progress information.
pgcompacttable --dbname billing --exclude-schema pgq
Compacts all bloated tables in the billing database and their bloated indexes excepts ones that are in the pgq schema.
pgcompacttable --dbname billing -t operations -f
Force compact table operations in database billing.
Notice, tables and indexes with bloat less than 20% (hardcoded MINIMAL_COMPACT_PERCENT constant) are considered normal and not processed until option --force
is taken.
pgcompacttable currently supports PostgreSQL starting from 9.2. Rebuilds partial indexes, functional, unique, used for foreign keys and indexes already placed on another tablespace are supported.
Unlike another popular tool pg_repack this tool has some advantages:
--delay-ratio
option)