https://pgbouncer.github.io/
https://pgbouncer.github.io/usage.html
https://www.pgbouncer.org/config.html
PgBouncer の設定 | Heroku Dev Center 2023
PostgreSQL + Rails へ PgBouncer を導入してDBメモリ使用量を大幅に改善した話 - Hello Tech 2023
FreeBSD
FreeBSD 10.1にpgbouncerをインストールする
https://symfoware.blog.fc2.com/blog-entry-1738.html
Possible solutions:
Reconnect after a certain number of requests
Add more memory
Connection pooling to put a ceiling on the number of postgres connections using pgpool-II or PgBouncerhttps://stackoverflow.com/questions/20514569/idle-postgres-processes-taking-up-lots-of-memory
pgbouncer log rotate
http://raghavt.blogspot.com/2016/08/how-to-rotate-pgbouncer-logs-in.html
FreeBSD newsyslog
/usr/local/etc/newsyslog.conf.d/pgbouncer /var/log/pgbouncer/pgbouncer.log pgbouncer:pgbouncer 644 7 * @T00 J /var/run/pgbouncer/pgbouncer.pid
max_client_conn pgbouncerが受け付けるコネクション数
pool_size pgbouncerとpostgresの間のコネクション数
pool_size コネクションを使い切った状態で、コネクション取得できず
query_wait_timeout 秒経過すると Pooler Error: query_wait_timeout
