pgFouine - a PostgreSQL log analyzer

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Installation instructions & Tutorial

Installation

You can either untar the pgFouine tarball or install the RPM package.

  • If you use the tarball, pgFouine is installed locally and can be run with ./pgfouine.php in the directory where you installed it.
  • If you install the RPM package, pgFouine is installed globally and you can run pgFouine with pgfouine.php.

How to enable query logging

PostgreSQL 8.x

Using syslog

Edit your postgresql.conf file (usually located in /var/lib/pgsql/data/) and set the following configuration directives:

  • To enable syslog logging:
    log_destination = 'syslog'
    redirect_stderr = off
    silent_mode = on
  • To log queries slower than n milliseconds:
    log_min_duration_statement = n
    log_duration = off
    log_statement = 'none'
    To log every query executed, set log_min_duration_statement to 0. Set it to -1 to disable query logging.

Then edit your /etc/syslog.conf to set up a PostgreSQL facility:

local0.*		-/var/log/pgsql

You should also ignore PostgreSQL facility for the default log file otherwise you will log the queries twice:

*.info;mail.none;authpriv.none;cron.none;local0.none                /var/log/messages

Restart syslogd and PostgreSQL.

Apart from the extra I/O, the overhead of logging is barely noticeable. You can set syslog to send the log to another server through the network with @ip.ad.dr.ess.

Filter on database and/or user with syslog

You can filter your log file on database and user using the -database and -user options. To do so, you need to configure the following log_line_prefix:

log_line_prefix = 'user=%u,db=%d '

Using stderr log file

Using the following configuration, you can log to stderr instead of syslog. This is not recommended as we cannot guarantee the consistency of statements if they are multilines.

log_destination = 'stderr'
redirect_stderr = on
log_line_prefix = '%t [%p]: [%l-1] '

Filter on database and/or user with stderr

You can filter your log file on database and user using the -database and -user options. To do so, you need to configure the following log_line_prefix:

log_line_prefix = '%t [%p]: [%l-1] user=%u,db=%d '

PostgreSQL 7.x

Edit your postgresql.conf file (usually located in /var/lib/pgsql/data/) and set the following configuration directives:

  • To log queries slower than n milliseconds:
    syslog = 2
    log_min_duration_statement = n
    log_duration = false
    log_statement = false
    
    To log every query executed, set log_min_duration_statement to 0. Set it to -1 to disable query logging.
  • To log queries slower than n milliseconds AND duration for ALL queries (it only works with PostgreSQL 7.x; pgFouine counts every duration only once):
    syslog = 2
    log_min_duration_statement = n
    log_duration = true
    log_statement = false

Then edit your /etc/syslog.conf to set up a PostgreSQL facility:

local0.*		-/var/log/pgsql

You should also ignore PostgreSQL facility for the default log file otherwise you will log the queries twice:

*.info;mail.none;authpriv.none;cron.none;local0.none                /var/log/messages

Restart syslogd and PostgreSQL.

Apart from the extra I/O, the overhead of logging is barely noticeable. You can set syslog to send the log to another server through the network with @ip.ad.dr.ess.

Usage

pgFouine is an easy to use command line tool. The following command generates an HTML report with all default options:

$ pgfouine.php -file your/log/file.log > your-report.html

The following command line displays a text report with only 10 queries in each list to the standard output:

$ pgfouine.php -file your/log/file.log -top 10 -format text

You can find more examples on the Sample reports page.

By using pgfouine.php -help, you can display the usage information.