linux – 如何为在Debian Jessie上运行的守护进程提高文件描述符

/etc/init.d/pgbouncer：

[... snip ...]
    case "$1" in
      start)
        # Check if we are still disabled in /etc/default/pgbouncer
        [ "${START:-}" = "0" ] && exit 0
        log_daemon_msg "Starting PgBouncer" $NAME
        test -d $PIDDIR || install -d -o postgres -g postgres -m 2775 $PIDDIR

        ### set whatever limits you want ###
        ulimit -n 20000

        $SSD --start --chuid $RUNASUSER --oknodo -- $OPTS 2> /dev/null
        log_end_msg $?
        ;;
    [... snip ...]

添加此行后,应在重新启动后发生效果：

这样做,或者你被大喊：

# systemctl daemon-reload

然后：

# /etc/init.d/pgbouncer restart

更新：

我的原始答案显示你可以在init脚本中添加“ulimit”,适用于Debian 8.尽管Deb8是一个systemd发行版,但是pgbouncer的默认安装仍然使用了init脚本.

对于使用systemd完全管理pgbouncer的Centos7,您希望使用systemd.service文件.

首先,在Centos7上pgbouncer的默认服务文件中似乎存在一个错误,你需要将“Type = forked”改为“Type = simple”.

在pgbouncer.service文件中,您还可以在[Service]部分添加“LimitNOFILE = ##”…

/etc/systemd/system/pgbouncer.service

    ## good practice to include the default service file as it may change with future updates
    .include /lib/systemd/system/pgbouncer.service

    ## change the Type= per this bug
    ## http://www.postgresql.org/message-id/554A7105.1050002@gmx.net
    Type=simple

    ## Add a service section and set the max number of open files
    [Service]
    LimitNOFILE=12345

可能值得验证打开文件的最大数量是瓶颈.您可以检查日志,实际上是“太多打开文件”错误消息.在我超过允许打开文件的最大数量的每种情况下,该过程都抱怨…

/var/log/postgresql/pgbouncer.log

ERROR S: login failed: FATAL: could not open relation mapping file (...): Too many open files in system
ERROR S: login failed: FATAL: could not open file (...): Too many open files in system
ERROR S: login failed: FATAL: pipe() failed: Too many open files in system
WARNING sbuf_connect failed: Too many open files in system

/var/log/postgresql/postgresql-9.4-main.log

LOG:  out of file descriptors: Too many open files in system; release and retry
PANIC:  could not open file (...): Too many open files in system
LOG:  server process (...) was terminated by signal 6: Aborted
DETAIL:  Failed process was running: END;
LOG:  terminating any other active server processes

我们不需要担心pgbench的可用FD,因为如果它们还不够,pgbench将无法运行：

$ulimit -S -n 100
$pgbench -h 192.168.122.69 -p 6432 -U postgres -d booktown -c 200 -t 10000
You need at least 202 open files but you are only allowed to use 100.
Use limit/ulimit to increase the limit before using pgbench.