Ubuntu Manpage: pgCluu - PostgreSQL Cluster utilization

NAME

       pgCluu - PostgreSQL Cluster utilization

DESCRIPTION

       pgCluu is a PostgreSQL performance monitoring and auditing tool.

       It is a Perl program used to perform a full audit of a PostgreSQL Cluster and System
       performance. It is divided in two parts:

       - A collector used to grab statistics on the PostgreSQL cluster using the psql command
       line utility and sar from the sysstat package.

       - A pure Perl grapher that will generate all HTML and charts output without any
       requirements.

       If you don't need system utilization reports or don't want to install the sysstat package,
       you can disable it at command line. You will only have reports about your PostgreSQL
       Cluster. If you are running pgCluu from a central server using option -h to monitor
       remotely a PostgreSQL Cluster, the call to sar is automatically disabled.

       If you just want to have system utilization reports or generate graphs from a sar data
       file, it's also possible.

SYNOPSIS

       PostgreSQL and System metrics collector.

               pgcluu_collectd [options] output_dir

       Report generator.

               pgcluu [options] -o report_dir input_dir

REQUIREMENT

       pgCluu comes with two Perl scripts. You need a modern Perl distribution, the psql client
       and the sar command line utility (sysstat). The sysstat package is optional, you can still
       use pgCluu to generate reports about your PostgreSQL Cluster without it.

       Charts are rendered using a Javascript library so you don't need anything else.  Your
       browser will do all the work.

INSTALLATION

Installation from package
Installation of pgCluu can be done through the PostgreSQL Global Development Group (PGDG)
repositories. See how to install the PGDG repositories at the following URLs for Debian
and Ubuntu:

https://wiki.postgresql.org/wiki/Apt

and Redhat, CentOs, Fedora, Scientific Linux and Oracle Enterprise Linux:

https://yum.postgresql.org/

Once it is done you can simply install pgCluu with commands:

sudo apt install pgcluu
sudo yum install pgcluu

Look at the package information to know where files are specifically installed. See next
two chapters to see which default installation paths are used.

Installation from sources
Download the tarball from GitHub and unpack the archive:

tar xzf pgcluu-3.x.tar.gz
cd pgcluu-3.x/
perl Makefile.PL
make && sudo make install

This will copy the Perl scripts pgcluu_collectd and pgcluu into /usr/local/bin directory
and the man page to /usr/local/share/man/man1/pgcluu.1p.gz. Those are the default
installation directories for 'site' install on some well-known distribution but the path
could change.

If you want to install all under /usr location, use INSTALLDIRS='vendor' as an argument of
Makefile.PL. The script will be installed into /usr/bin/pgcluu and the manpage into
/usr/share/man/man1/pgcluu.1p.gz.

For example, to install everything just like Debian does, proceed as follows:

perl Makefile.PL INSTALLDIRS=vendor

By default INSTALLDIRS is set to site.

The directory where statistics will be saved is /var/lib/pgcluu/data and the default
directory for reports is /var/lib/pgcluu/report.

The CGI script is installed into /var/lib/cgi-bin/pgcluu.cgi and the Apache configuration
file into /etc/apache/conf-available/pgcluu.conf. This file allow acces to resources files
(CSS and JS files) from installation directory /usr/local/share/pgcluu/rsc/. Access is
granted to local user only by default.

All scripts (pgcluu_collectd, pgcluu and pgcluu.cgi) are reading configuration file from
/usr/local/etc/pgcluu.conf. This file is mainly use by the CGI script but some directives
are dedicated to pgcluu_collectd and pgcluu script to define the retention days for
example.

Custom installation
The installation of pgCluu can be fully customized through environment variables
(RSCDIR,CGIDIR,CONFDIR,PIDDIR,STATDIR,APACHECONF,MANDIR, DOCDIR,SYSTEMDDIR,RETENTION).
These variables are passed to Makefile.PL as command line arguments or can be exported as
environment variables before running "perl Makefile.PL".

The default values for these variables are:

DESTDIR => /usr/local
INSTALLDIRS => site
CONFDIR => DESTDIR/etc
PIDDIR => /var/run/postgres
STATDIR => /var/lib/pgcluu/data
REPORTDIR => /var/lib/pgcluu/data
RSCDIR => DESTDIR/share/pgcluu
CGIDIR => /usr/lib/cgi-bin
APACHECONF => /etc/apache2/conf-available
MANDIR => DESTDIR/share/man
DOCDIR => DESTDIR/share/doc
SYSTEMDIR => DESTDIR/lib/systemd/system
RETENTION => 0

If INSTALLDIRS is set to 'vendor':

CONFDIR => /etc
DESTDIR => /usr

The configuration file is auto-generated by the Makefile.PL script and saved into
CONFDIR/pgcluu.conf. If the destination file exists it is not overridden. The file is also
saved as example in the directory DOCDIR/pgcluu/examples/pgcluu.conf.dist

The directory where pgcluu_collectd will store statistics is defined with STATDIR which is
by default /var/lib/pgcluu/data. The directory where pgcluu will generate static html
reports is defined by REPORTDIR. The default is /var/lib/pgcluu/report. Both directory
must be owned by the postgres user.

The man page is saved as DESTDIR/share/man/pgcluu.1p.gz and a symbolic link
pgcluu_collectd.1p.gz is created to this file. The documentation, README, changelog.gz,
LICENSE files are saved under DESTDIR/share/doc/.

For the CGI mode, the resources (css and js files from the cgi-bin/rsc) are saved under
the DESTDIR/share/pgcluu/rsc directory. The CGI script is saved under
/usr/lib/cgi-bin/pgcluu.cgi. The Apache configuration file under
/etc/apache2/conf-available/pgcluu.conf with a symbolic link
/etc/apache2/conf-enabled/pgcluu.conf created to this file. Its content:

Alias /pgcluu RSCDIR/
<Directory RSCDIR/>
Options FollowSymLinks MultiViews
AllowOverride None
Require local
#Require ip 192.1.168.0/24
</Directory>

The systemd files (pgcluu_collectd.service,pgcluu.service,pgcluu.timer) are saved as
examples into DOCDIR/pgcluu/examples/ and into the systemd directory SYSTEMDDIR/

The right path to the configuration file is set into all scripts pgcluu, pgcluu_collectd
and pgcluu.cgi. The path where the pid file must be saved is replaced into pgcluu_collectd
with the value of PIDFILE variable.

Paths to scripts, pid directory, statistics and reports are replaced in all systemd
service files following the values of the environment variable explain here.

USAGE

       Manually

       See next two chapters for a complete description of the command line options.  For the
       impatient, here some simple commands that could be run as postgres user:

               mkdir /tmp/stat_db1/
               pgcluu_collectd -D -i 60 /tmp/stat_db1/
               LOG: Detach from terminal with pid: 11323

       or with more options

               pgcluu_collectd -D -i 60 /tmp/stat_db1/ -h 10.10.1.1 -U postgres -d mydb
               LOG: Detach from terminal with pid: 14671

       wait some time and activity on your PostgreSQL Cluster...  Then stop the pgcluu_collectd
       daemon and generate the report:

               pgcluu_collectd -k
               LOG: Received terminating signal.
               mkdir /tmp/report_db1/
               pgcluu -o /tmp/report_db1/ /tmp/stat_db1/

       You should obtain something like example at http://pgcluu.darold.net/example/

       By default all javascript, css and the webfont fontawesome are automatically generated
       into the output directory if those files does not already exits.

       Using systemd unit files

       pgcluu comes with systemd service files:

           - pgcluu_collectd.service: execute pgcluu_collectd as a daemon to collect statistics.
           - pgcluu.service: execute pgcluu to generate reports.
           - pgcluu.timer: run periodically pgcluu.service

       These files are installed automatically by the install script or the package into
       /lib/systemd/system/. To activate these services proceed as follow:

               systemctl daemon-reload
               systemctl enable pgcluu_collectd.service
               systemctl enable pgcluu.service
               systemctl enable pgcluu.timer
               systemctl start pgcluu_collectd.service
               systemctl start pgcluu.timer

       Be warn that storing indefinitely statistics with pgcluu_collectd can fill you disk space
       in the short or medium term. You have to remove obsolete statistics manually using a cron
       job or using the embedded retention feature by adding option '--retention ndays' to
       pgcluu_collectd call or by changing the value of STATS_COLLECTD_RETENTION configuration
       directive in file /usr/local/etc/pgcluu.conf or /etc/pgcluu.conf file following your
       installation.  You can also set STATS_REPORT_RETENTION to limit the retention of reports
       directories or use option '--retention ndays' with pgcluu. Default is to preserve
       collected data for the past 30 days.

       If you want to use the CGI mode you also have activate pgcluu caching by enabling value
       STATS_REPORT_CACHING in the configuration file and using pgcluu.service+pgcluu.timer. If
       you don"t want to use systemd you can simply run pgcluu script with the -C option and
       execute it periodically through a cron job.

       Note that the systemd service files set the privilege to the data and report directory to
       user postgres and group www-data. By this way reports are readable through an httpd server
       for static reports and data are readable through the CGI if enabled. Command executed by
       the pgcluu_collectd.service file (daemon part) are:

               /bin/mkdir -p $STATDIR
               /bin/chown postgres:www-data $STATDIR
               /bin/chmod u=rwX,g=rsX,o= $STATDIR

       The pgcluu.service file (client part) execute commands:

               /bin/mkdir -p $REPORTDIR
               /bin/chown postgres:www-data $REPORTDIR
               /bin/chmod u=rwX,g=rsX,o= $REPORTDIR

       In case you don't want to use systemd service files you will have to execute these
       commands manually before tunning pgCluu.

       For pgcluu reports, the output directory can be defined in the configuration file using
       the STATS_REPORT_OUTDIR directive.

COLLECTING STATISTICS

To generate reports about your PostgreSQL Cluster Utilization you must collect statistics
before. pgcluu_collectd is here for that. It can be run in a daemon mode (option -D) or in
interactive mode for debugging purpose. All you need is to provide a directory where data
will be stored. Statistics will be pooled at a default interval of 60 seconds, using
option -i you can customize it. See below for a complete list of command line options.

pgcluu_collectd usage
usage: pgcluu_collectd [options] output_dir

output_dir: full path to directory where pgcluu_collectd will
store statistics.

options:

-B, --enable-buffercache enable buffercache statistics if pg_buffercache
extension is installed.
-c, --capture create a snapshot of the PostgreSQL installation
into tmp/pgcluu_capture.tar.gz.
-C, --end-counter=NUM terminate program after NUM reports.
-d, --dbname=DATABASE database name to connect to. Default to current user.
-D, --daemonize detach from console and enter in daemon mode.
-E, --end-after=NUM self terminate the program after a given number of
seconds. Can be written: 7200 or 120M or 2H, for
days use 7D for example to stop collecting data
after seven days.
-f, --pid-file=FILE path to pid file. Default: /var/run/postgresql/pgcluu_collectd.pid.
-h, --host=HOSTNAME database server host or socket directory
-i, --interval=NUM time to wait between runs
-k, --kill stop current pgcluu_collectd running daemon.
-m, --metric=METRIC set a coma separated list of metrics to perform.
-M, --max-size=SIZE self terminate program when the size of the output
directory exceed a given size. Can be written: 2GB
or 2000MB.
-n, --no-pg_stats-dump don't collect statistics from the pg_stats view.
-p, --port=PORT database port(s) to connect to. Defaults to 5432.
-P, --psql=BIN path to the psql command. Default: psql.
-Q, --no-statement do not collect statistics from pg_stat_statements.
-r, --rotate-daily force daily rotation of data files.
-R, --rotate-hourly force hourly rotation of data files.
-s, --sar=BIN path to sar sysstat command. Default: sar.
-S, --disable-sar disable collect of system statistics with sar.
-t, --lock-timeout=NUM terminate metric SQL query after N second in case it
wait too much time because of a lock. Default: 3
-T, --no-tablespace disable lookup at tablespace when the connect user
is not superuser to avoid printing an error message.
-U, --dbuser=USERNAME database user to connect as. Default to current user.
-v, --verbose Print out debug informations.
-V, --version Show pgcluu_collectd version and exit.
-w, --no-waitevent don't collect wait event stats from pg_wait_sampling.
-W, --password=pass database password.
-z, --compress force compression of rotated data files.
--included-db=DATABASE collect statistics only for those databases present
in a comma separated list of database names.
--list-metric list available metrics actions that can be performed.
--sysinfo get operating system infos and exit (sysinfo.txt).
--no-sysinfo do not collect operating system information at all.
--no-database do not collect database statistics at all.
--pgbouncer-args=OPTIONS Option to used to connect to the pgbouncer system
database. Ex: -p 6432 -U postgres -h 192.168.1.100
You must at least give one parameter to enable
pgbouncer monitoring.
--sar-file=FILE path to sar output data file for sysstat stats
Default to output_dir/sar_stats.dat.
--stat-type all|user Set stats tables to read. Values: 'all' or 'user' to
look at pg_stat_(all|user) tables. Default: user.
--pgversion X.Y force the PostgreSQL version to the given value.
--pgservice NAME Name of service inside of the pg_service.conf file.
--exclude-time RANGE exclude a laps of time by giving the start and end
hours.
--cron-user=USERNAME collect crontab settings for the given username (in
this case pgcluu_collectd need to be run as root).
Default is to use USERNAME environment variable or
postgres when it is not defined.
--package-list=CMD command to list PostgreSQL packages. Default is to
autodetect package type and using command 'rpm -qa'
or 'dpkg -l'. If you have an other system you can
set a custom command. A filter on keyword 'postgres'
is appended to the command: ' | grep postgres'.
--retention NDAYS number of rolling days to keep in data directory in
incremental mode. Default is to store indefinitely.
--disable-pidstat do not collect metrics from pidstat command.
--help print usage

Use those options to execute sar on the remote host defined by the -h option, otherwise it
will be executed locally:

--enable-ssh activate the use of ssh to run sysstat remotely.
--ssh-program ssh path to the ssh program to use. Default: ssh.
--ssh-user username connection login name. Default to running user.
--ssh-identity file path to the identity file to use.
--ssh-timeout second timeout to ssh connection failure. Default 10.
--ssh-options options list of -o options to use for the ssh connection.
Options always used:
-o ConnectTimeout=$ssh_timeout
-o PreferredAuthentications=hostbased,publickey

For example, as postgres user to monitor locally a full PostgreSQL cluster:

mkdir /tmp/stat_db1/
pgcluu_collectd -D -i 60 /tmp/stat_db1/

to collect statistics from pgbouncer too, and limit database statistics to a single
database:

pgcluu_collectd -D -i 60 /tmp/stat_db1/ -h 10.10.1.1 -U postgres -d mydb
--pgbouncer-args='-p 5342'

to disable statistics collect between 22:30 and 06:30 the next day:

pgcluu_collectd -D -i 60 /tmp/stat_db1/ --exclude-time "22:30-06:30"

to collect statistics from a remote server:

pgcluu_collectd -D -i 60 /tmp/statdb1/ -h 10.0.0.1 -U postgres --disable-sar

the same but with collecting system statistics using remote sar calls:

pgcluu_collectd -D -i 60 /tmp/statdb1/ -h 10.0.0.1 -U postgres --enable-ssh
--ssh-user postgres --ssh-identity /var/lib/postgresql/.ssh/id_rsa.pub

You may need a .pgpass and be able to establish passwordless ssh connections to be able to
collect statistics from remote hosts.

Then after some time and activities on the database, stop the daemon as follow:

pgcluu_collectd -k

or by sending sigterm to the pgcluu_collectd's pid.

You can run the collector in incremental mode using a daily or a hourly statistics
rotation:

pgcluu_collectd -D -i 60 /tmp/stat_db1/ --rotate-daily

On a server with huge activity you may want to use --rotate-hourly and compression mode
with --compress option. If you have limited disk space you can restrict the retention time
of statistics files using option --retention with the storage day limit.

Statistics files
The output directory with all statistics collected should look likes:

Then now you can proceed with pgcluu to generate reports.

Additional statistics from extensions
To be able to report top statements, wait events and subxact statistics you need to create
the related extensions into a single database and use this database for primary connection
to pgcluu_collectd using the -d option.

The related extension are pg_stat_statements, pg_wait_sampling and pg_subxact_counters.

Rotation and compression
When used the --rotate-daily or --rotate-hourly commands line option will force
pgcluu_collectd to rotate daily or hourly all statistic's files. In this case, statistics
files will be created in a subdirectory based on rotation frequency,
output_dir/year/month/day[/hour]. This is called the incremental mode.

To save filesystem space it is possible to enable compression of all rotated files during
the rotation process. Just activate the -z or --compress command line option. You can also
use the --retention option to set the storage time limit in days.

Incremental mode
This mode is enabled when --rotate-daily or --rotate-hourly command line options are used.
It allow pgcluu to build reports incrementally by days or hours. In this mode you don't
have to build reports per day or hour pgcluu will do the work automatically, just give it
the top statistics directory.

pgcluu -o /var/www/pgcluu/reports/ /var/lib/pgcluu/data/

pgcluu will detect that --rotate-daily or --rotate-hourly have been used to collect data
and generate reports for each day or hours stored. Previous directories already processed
will not be processed again unless this was the the last one.

The daily or hourly basis statistic storage also allow the use of the CGI script
pgcluu.cgi to have dynamic reports and temporal search. See "Using dynamic mode" chapter.

When used the --rotate-daily or --rotate-hourly commands line option will force
pgcluu_collectd to rotate daily or hourly all statistic's files. In this case, statistics
files will be created in a subdirectory based on rotation frequency,
output_dir/year/month/day[/hour]. This is called the incremental mode.

Capture mode
The goal of this mode is to be able to obtain a simple report about the PostgreSQL
installation without collected metrics others than database and tablespace size. This
report can be use by ITs to better understand the configuration and things that need to be
tuned.

To enable this mode, just run pgcluu_collectd with the single option -c or --capture.
Other command line options will not be taken in account. pgcluu_collectd will create e
temporary directory /tmp/pgcluu_capture to store temporary data and will removed if after
building a compressed tar archive: /tmp/pgcluu_capture.tar.gz. This is this archive that
can be used with pgcluu to build a snapshot report of the instance. pgcluu will
automatically detect this mode.

GENERATING REPORTS

Static HTML reports
To generate a pgCluu report about a PostgreSQL Cluster you must, at least, have a
directory that contains all data files generated by pgcluu_collectd or pgstats. In this
directory, if you have a file named sar_stats.dat or sadc_stats.dat for binary sadc data
file, it will be taken to build report about system utilization. If you just want to make
a report from a sar file use the -i or -I options.

usage: pgcluu [options] [-i sar_file | -I sadc_file] [input_dir]

input_dir: directory where pgcluu_collectd or pgstats and sar data
files are stored.

options:
-b, --begin datetime start date/time for the data to be parsed (time of current
timezone).
-C, --cache generate cache files only (.bin), no html output.
-d, --db-only dbname only report for the whole cluster and the given
database name. You can use it multiple time or
give a comma separated list of database name.
-D, --device-only dev only report I/O stats for a particular device
You can use it multiple time or give a comma
separated list of device name, ex: sda,sdc.
-e, --end datetime end date/time for the data to be parsed (time of current
timezone).
-i, --sar-file=FILE path to the sar text data file to read to generate
system reports. Default to input_dir/sar_stats.dat.
-I, --sadc-file=FILE sadc binary data file to read to generate system
reports. Default to input_dir/sadc_stats.dat.
-n, --top-number Top number of tables or indexes I/O stats to show.
Default is set to top 10. Set it to 0 to show all.
-N, --network-only iface only report stats for a particular network interface.
You can use it multiple times or give a comma separated
list of network interfaces, ex: eth0,eth1.
-o, --output=DIR output directory
-r, --reverse-date By default pgcluu look at mm/dd/yy format in sar file.
When enabled pgcluu will look at dd/mm/yy format.
-s, --sadf=BIN path to the sadf sysstat command used to read the
sadc binary data file. Default: /usr/bin/sadf.
-S, --disable-sar disable collect of system statistics with sar.
-t, --with-table table Only report for the whole tables and the given
table name. You can use it multiple time or
give a comma separated list of database name.
-T, --no-table Do not report statistics related to tables.
-v, --verbose Print out debug informations.
-V, --version Show pgcluu version and exit.
-x, --external-menu Save menu in menu.html and load it into each report
using w3-include-html attribut from w3.js. This will
only work if acces to HTML reports is through a Web
server, not using the file:// protocol.
-z, --timezone +/-XX Set the number of hour(s) from GMT of the timezone,
Eg: -z +02
Usually autodetected.
Use this to adjust date/time from the sar output,
pgcluu use GMT time to draw charts.
-Z, --stats-timezone +/-XX Set the number of hour(s) from GMT of the timezone.
Eg: -Z +02
Usually autodetected.
Use this to adjust date/time from the cluster and
system stats output, pgcluu use GMT time.
--from-sa-file instruct pgcluu that file specified by the -i option
uses the standard system activity daily data file.
--charset used to set the HTML charset to be used.
Default: utf-8.
--retention NDAYS number of rolling days to keep in report directory.
Default is to store indefinitely.
--help print usage

For example, you can generate all HTML reports from data files stored into /tmp/stat_db1/
with the following commands:

mkdir /tmp/report_db1/
pgcluu -o /tmp/report_db1/ /tmp/stat_db1/

If you just want reports of some databases, use the following:

pgcluu -o /tmp/report_db1/ /tmp/stat_db1/ --db-only "db1,db2,db3"

If you just want to create a report from a sar output file:

sar -p -A 10 60 > /root/my_sar_file.txt
pgcluu -o /tmp/report_sar/ -i /root/my_sar_file.txt

or from a daily sa file:

sar -p -A -f /var/log/sa/sa18 > /root/my_sar_file.txt
pgcluu -o /tmp/report_sar/ -i /root/my_sar_file.txt --from-sa-file

and from a sa binary file:

pgcluu -o /tmp/report_sar/ -i /var/log/sysstat/sa22

or the sa text file if you don't have the same version of sysstat:

pgcluu -o /tmp/report_sar/ -i /var/log/sysstat/sar23 --from-sa-file

If pgcluu_collectd have been run in incremental mode you can limit the number of retention
days used for the reports:

pgcluu -o /tmp/report_sar/ /tmp/stat_db1/ --retention 30

A static report will be built for each day or hour following the rotation used with
pgcluu_collectd.

Dynamic reports (CGI)
Dynamics reports are build by a CGI script named pgcluu.cgi that can be found in the cgi-
bin repository of the source code. It allow you to select the time period to build reports
and to look at all differents reports for this period just as with static HTML reports.
After installation from sources or binary packages the CGI might be found in
/usr/lib/cgi-bin/pgcluu.cgi or /var/www/cgi-bin/pgcluu.cgi following your distribution.

To use pgCluu in CGI mode, you need a Web server (here we use Apache) and a cron task to
build the cache periodically.

First enable CGI mode.

sudo a2enmod cgi
sudo service apache2 restart

Then the CGI need to find the statistics directory where pgcluu_collectd mostly
/var/lib/pgcluu/data/. The content of this repository must be readable by the Apache user
(www-data).

Take care to restrict access to your server and the CGI as information about your database
and server are exposed in the reports.

The CGI script, pgcluu.cgi, use resources files (CSS and javascript). They are stored in
the cgi-bin/rsc/ directory of the source distribution. Install this repository onto the
DocumentRoot of your Web server, for example:

sudo mkdir /var/www/pgcluu/
sudo cp -rf cgi-bin/rsc /var/www/pgcluu/

Then edit /etc/pgcluu.conf, copy it from sources cgi-bin/pgcluu.conf if it doesn't exists.
Change the RSC_BASE and INPUT_DIR configuration directive to match your installation. Here
in our example:

RSC_BASE /pgcluu/rsc/
INPUT_DIR /var/lib/pgcluu/data

Now we can start the data collection. For the moment pgcluu.conf is only read by the CGI
pgcluu.cgi but this might change in the future.

To let pgCluu start collecting data, you can use the following command (you can change it
to however you like). We will need postgres user for this.

sudo su - postgres
/usr/local/bin/pgcluu_collectd -D -i 60 --rotate-daily /var/lib/pgcluu/data

This will rotate you data daily. This is also the default in the systemd service file.

Plugging the CGI directly to the CSV statistics files will result in very slow generation
reports. To improve speed caching must be used, you must execute periodically pgcluu in
cache mode. Run it manually the first time

/usr/local/bin/pgcluu --cache /var/lib/pgcluu/data

then add a cron task to execute the command each five or ten minutes:

*/5 * * * * /usr/local/bin/pgcluu --cache /var/lib/pgcluu/data

If you are using systemd pgcluu.timer service then caching can be enabled using
STATS_REPORT_CACHING directive. Enabling this mode generate cache files (*.bin) in the
statistics directory and disable static HTML reports generation.

To see your reports, go to the following URL:

http://localhost/cgi-bin/pgcluu.cgi

Or change localhost by your fqdn server name.

Note that here pgcluu_collectd and pgcluu scripts are found in /usr/local/bin/ which is
the default for an installation from sources but with an installation from binary package
you might find them into /usr/bin/.

The CGI mode allow you to select the period of time used to generate the statistics
reports. Using default pgcluu_collectd 60 seconds interval, a daily graph will have 1440
points. Having too much timeseries to render is not a good point for performances so we
are limiting to the first seven days of the selected period. This mean a maximum of 10080
points for one week, this seems a safe limit. Feel free to increase or reduce the limit
following the server and client resources. This is controlled by

MAX_RENDERED_DAYS 7

configuration directive in pgcluu.conf

LICENSE

       Copyright (c) 2012-2024, Gilles Darold

       pgCluu is licenced under the PostgreSQL Licence a liberal Open Source license, similar to
       the BSD or MIT licenses. That mean that all parts of the program are open source and free
       of charge.

               Permission to use, copy, modify, and distribute this software and its
               documentation for any purpose, without fee, and without a written agreement
               is hereby granted, provided that the above copyright notice and this
               paragraph and the following two paragraphs appear in all copies.

               IN NO EVENT SHALL Dalibo BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
               SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,
               ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
               Dalibo HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

               Gilles Darold SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
               LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
               PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS,
               AND Gilles Darold HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT,
               UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

       This is the case for both, pgcluu_collectd and the grapher pgcluu programs.

AUTHORS

       pgCluu is an original development of Gilles Darold.

       Some parts of the collector are taken from pgstats a C program writen by Guillaume Lelarge
       and especially the SQL queries including the compatibility with all PostgreSQL versions.
       See https://github.com/gleu/pgstats

       Btw pgCluu grapher is compatible with files generated by pgstats, sar and sadc so you can
       use it independantly to graph those data. Some part of the sar output parser are taken
       from SysUsage. See http://sysusage.darold.net/