Postgres
Sommaire |
PG -- PostgreSql
Streaming Replication
Fichiers de config
Le param "config_file" permet de changer le PATH vers le postgresql.conf (i.e. ne pas ne le mettre dans le DATADIR) et donc du streaming.cong (un include) c'est un param à passer dans le ligne de commande du binaire. Donc dans le script d'init.
Il passe très bien dans le -D de l'init et si le data_directory est bien set dans le postgresql.conf
postgresql.conf streaming.conf => include dans le postgresql.conf contient les conf spécifiques au streaming recovery.conf => les param pour que le slave (standby) sache aller se remonter à partir du master.
faut tester un peut plus tout ça ....
[DOC PG -> http://www.postgresql.org/docs/9.0/static/warm-standby.html#STREAMING-REPLICATION]
"Streaming replication is asynchronous, so there is still a small delay between committing a transaction in the primary and for the changes to become visible in the standby. The delay is however much smaller than with file-based log shipping, typically under one second assuming the standby is powerful enough to keep up with the load. With streaming replication, archive_timeout is not required to reduce the data loss window."
WAL
http://www.postgresql.org/docs/9.0/static/wal-configuration.html
les tablespace
Il faut absolument créer les dossiers avant de faire le CREATE TABLESPACE tbsp DIRECTORY '/path/to/dir/' SUR LES SLAVES AUSSI !!!
Utiles
taille des bases
psql -U postgres -c "SELECT datname, pg_size_pretty(pg_database_size(datname)) from pg_database ;"
la taille des index
postgres=# select pg_size_pretty(pg_total_relation_size('tableXX') - pg_relation_size('tableXX'));
#!/bin/bash
for base in `psql -c "select datname from pg_database;" | grep -v "datname" |grep -v \- |grep -v "rows"|grep -v "postgres"`;
do
echo "#############"
echo $base
echo "#############"
for table in `psql $base -c "\d"| grep -v "List of relations" |grep -v + |grep -v rows |grep -v Name |cut -d "|" -f 2`;
do echo $table;
psql $base -c "select pg_size_pretty(pg_total_relation_size('$table') - pg_relation_size('$table'));";
echo "+++++++++++++++++";
done
done
Utiles
show processlist => select * from pg_stat_activity; desc => \d
stress
postgres=# CREATE DATABASE damien; postgres=# \c damien You are now connected to database "damien" as user "postgres". damien=# CREATE TABLE damien ( id varchar(55)); ou alors => damien=# CREATE TABLE damien ( id varchar(55)) TABLESPACE table_space_name; CREATE TABLE damien=# INSERT INTO damien select generate_series(1,1000000000);
