使用PostgreSQL的Rails每次請求重新連接多次

我最近遇到了一個問題，Rails將連接丟到我的PostgreSQL上，導致每個請求發生多次重新連接，從而顯着減慢請求速度。我目前運行在Mac OS X的一切地方有以下環境：使用PostgreSQL的Rails每次請求重新連接多次

的Mac OS X 10.8（山獅）
戰俘
NGINX（SSL解包 - 相同的應用程序重新連接行爲，即使沒有啓用此功能）通過自制
的PostgreSQL 9.2.2
的Rails 3.2.11

這是我database.yml：（數據庫和用戶名節錄）

development: 
    adapter: postgresql 
    encoding: unicode 
    database: <database> 
    pool: 5 
    username: <user> 
    password:

這是development.log一個典型的請求時的輸出：（具體型號，並呈現節錄）

Connecting to database specified by database.yml 


Started GET "/" for 127.0.0.1 at 2013-02-05 12:25:38 -0800 
Processing by HomeController#index as HTML 
    ... <app performs model loads and render calls> 
Completed 200 OK in 314ms (Views: 196.0ms | ActiveRecord: 60.9ms) 
Connecting to database specified by database.yml 
Connecting to database specified by database.yml

我也啓用語句記錄在Postgres而言，要在給定的請求期間更好地洞察數據庫端到底發生了什麼。下面是postgresql-<date>.log輸出：（查詢具體到我的應用程序刪節）

LOG: connection received: host=[local] 
LOG: connection authorized: user=<user> database=<database> 
LOG: statement: set client_encoding to 'UTF8' 
LOG: statement: set client_encoding to 'unicode' 
LOG: statement: SHOW client_min_messages 
LOG: statement: SET client_min_messages TO 'panic' 
LOG: statement: SET standard_conforming_strings = on 
LOG: statement: SET client_min_messages TO 'notice' 
LOG: statement: SET time zone 'UTC' 
LOG: statement: SHOW TIME ZONE 
LOG: statement: SELECT 1 
LOG: statement: SELECT 1 
    ... <app makes queries for request> 
LOG: disconnection: session time: 0:00:01.346 user=<user> database=<database> host=[local] 
LOG: connection received: host=[local] 
LOG: connection authorized: user=<user> database=<database> 
LOG: statement: set client_encoding to 'UTF8' 
LOG: statement: set client_encoding to 'unicode' 
LOG: statement: SHOW client_min_messages 
LOG: statement: SET client_min_messages TO 'panic' 
LOG: statement: SET standard_conforming_strings = on 
LOG: statement: SET client_min_messages TO 'notice' 
LOG: statement: SET time zone 'UTC' 
LOG: statement: SHOW TIME ZONE 
LOG: statement: SELECT 1 
LOG: connection received: host=[local] 
LOG: connection authorized: user=<user> database=<database> 
LOG: statement: set client_encoding to 'UTF8' 
LOG: statement: set client_encoding to 'unicode' 
LOG: statement: SHOW client_min_messages 
LOG: statement: SET client_min_messages TO 'panic' 
LOG: statement: SET standard_conforming_strings = on 
LOG: statement: SET client_min_messages TO 'notice' 
LOG: statement: SET time zone 'UTC' 
LOG: statement: SHOW TIME ZONE 
LOG: statement: SELECT 1 
LOG: statement: SELECT 1 
LOG: statement: SELECT 1 
LOG: disconnection: session time: 0:00:00.750 user=<user> database=<database> host=[local] 
LOG: disconnection: session time: 0:00:00.733 user=<user> database=<database> host=[local]

我很高興與相關CONFIGS更新的日誌記錄或命令調用輸出。另外，爲什麼所有的SELECT 1調用？他們的目的是什麼？

謝謝！

來源

2013-02-05 Seth V

答案是將PostgreSQL升級到更新的版本。我剛剛從原始問題中使用的9.2.2升級到9.2.4，問題完全消失，預期的性能特徵返回到我的開發應用程序。

來源

2013-05-05 09:11:42

使用PostgreSQL的Rails每次請求重新連接多次

回答

相關問題