请问各位的硬件是什么情况？我在 VMware 虚拟机里都比这快得多。

关掉spam的check，速度就马上起来了，只有168ms左右。

The $sa_mail_body_size_limit sets a limit on a mail size beyond which SpamAssassin is not called, so it can not contribute to memory usage much beyond this limit, times a small factor (2-5?, due to multiple internal representations of a message). If the $sa_mail_body_size_limit is large, and MTA mail size is not limited, or if mail has a huge mail header, the memory footprint can become noticable. For the rest of a lifetime the child process that processed the mail stays at its high virtual memory size. If this happens frequently, host resources may become scarce. Limiting the number of tasks is very much desirable in this case.

比较奇怪的是，英文论坛里没有用户反馈这个问题，而且自 07 年以来都没有这样的反馈。我还不是很确定到底是个别情况，还是所有用户都有这样的问题。抱歉。

大家可以尝试这样的临时解决方案：对外发的邮件不做 spam 和病毒扫描。具体的做法是：

- 在 /etc/amavisd/amavisd.conf （因为 Linux 发行版和版本的不同，配置文件位置可能有所不同），找到以下一段：

$policy_bank{'MYUSERS'} = {
    ...
    # don't perform spam/virus/header check.
    #bypass_spam_checks_maps => [1],
    #bypass_virus_checks_maps => [1],
    #bypass_header_checks_maps => [1],

    # allow sending any file names and types
    #bypass_banned_checks_maps => [1],
};

- 将这里的几个 bypass_ 参数的注释符号都去掉。去掉后看起来像下面这样：

$policy_bank{'MYUSERS'} = {
    ...
    # don't perform spam/virus/header check.
    bypass_spam_checks_maps => [1],
    bypass_virus_checks_maps => [1],
    bypass_header_checks_maps => [1],

    # allow sending any file names and types
    bypass_banned_checks_maps => [1],
};

修改完后请重启 Amavisd 服务。

如果仍存在同样的问题，请大家继续在这个帖子里回复。

这么说是 virus scanning 时比较慢，而不是 SpamAssassin 的 spam scanning。

$policy_bank{'MYUSERS'} = { ... # don't perform spam/virus/header check. bypass_spam_checks_maps => [1], bypass_virus_checks_maps => [1], bypass_header_checks_maps => [1], # allow sending any file names and types bypass_banned_checks_maps => [1], };