Rack/Rails Settings
Table of Contents
Ruby Path | Run-Time Mode | Max Connections | Environment | Initial Request Timeout (secs) | Retry Timeout (secs) | Keep Alive Timeout (secs) | Response Buffering | Max Idle Time | Back Log | Run On Start Up | Priority | 内存软限制 | 内存硬限制 | 进程软限制 | 进程硬限制
Ruby Rack/Rails Settings⇑
Description
Default configurations for Ruby Rack/Rails applications.
Ruby Path⇑
Description
Specifies path to Ruby executable. Generally, it is /usr/bin/ruby or /usr/local/bin/ruby depending on where Ruby has been installed to.
Syntax
绝对路径
Run-Time Mode⇑
Description
Specifies which mode Rack/Rails will be running as: "Development", "Production", or "Staging". The default is "Production".
Syntax
Select from drop down list
Max Connections⇑
Description
Specifies the maximum number of concurrent connections that can be established between the server and an external application. This setting controls how many requests can be processed concurrently by an external application, however, the real limit also depends on the external application itself. Setting this value higher will not help if the external application is not fast enough or cannot scale to a large number of concurrent requests.
Syntax
无符号整数
Tips
Setting a high value does not directly translate to higher performance. Setting the limit to a value that will not overload the external application will provide the best performance/throughput.
Environment⇑
Description
Specifies extra environment variables for the external application.
Syntax
Key=value. Multiple variables can be separated by "ENTER"
Initial Request Timeout (secs)⇑
Description
Specifies the maximum time in seconds the server will wait for the external application to respond to the first request over a new established connection. If the server does not receive any data from the external application within this timeout limit, it will mark this connection as bad. This helps to identify communication problems with external applications as quickly as possible. If some requests take longer to process, increase this limit to avoid 503 error messages.
Syntax
无符号整数
Retry Timeout (secs)⇑
Description
Specifies the period of time that the server waits before retrying an external application that had a prior communication problem.
Syntax
无符号整数
Keep Alive Timeout (secs)⇑
Description
Specifies the maximum time to keep an idle persistent connection open. When set to "-1", the connection will never timeout. When set to greater than or equal to 0, the connection will be closed after this time in seconds has passed.
Syntax
int
Response Buffering⇑
Description
Specifies whether to buffer responses received from external applications. If a "nph-" (Non-Parsed-Header) script is detected, buffering is turned off for responses with full HTTP headers.
Syntax
Select from drop down list
Max Idle Time⇑
Description
Specifies the maximum idle time before an external application is stopped by the server. When set to "-1", the external application will not be stopped by the server. The default value is "-1". This feature allows resources used by idle applications to be freed. It is especially useful in the mass hosting environment when you need to define many applications running in "setuid" mode for the sake of maximum security.
Syntax
Select from radio box
Tips
This feature is especially useful in the mass hosting environment. In order to prevent files owned by one virtual host from being accessed by the external application scripts of another virtual host, mass hosting often requires many different applications running at the same time in SetUID mode. Set this Max Idle Time low to prevent these external applications from idling unnecessarily.
Back Log⇑
Description
Specifies the backlog of the listening socket. Required if Auto Start is enabled.
Syntax
无符号整数
Run On Start Up⇑
Description
Specifies whether to start the external application at server start up. Only applicable to external applications that can manage their own child processes and where Instances value is set to "1". If enabled, external processes will be created at server startup instead of run-time.
Syntax
Select from radio box
Tips
If the configured external process has significant startup overhead, like a Rails app, then this option should be enabled to decrease first page response time.
Priority⇑
Description
Specifies priority of the external application process. Value ranges from -20 to 20. A lower number means a higher priority. An external application process cannot have a higher priority than the web server. If this priority is set to a lower number than the server's, the server's priority will be used for this value.
Syntax
int
See Also
Server 优先级
内存软限制⇑
Description
以字节为单位指定服务器启动的外部应用进程或程序的内存占用限制。
此限制的目的主要是为了防范软件缺陷或蓄意攻击造成的过度内存使用, 而不是限制正常使用。确保留有足够的内存,否则您的应用程序可能故障并 返回503错误。限制可以在服务器级别或独立的外部应用程序级别设置。如 果未在独立的外部应用程序级别设定限制,将使用服务器级别的限制。
如果在两个级别都没有设置该限制,或者限制值设为0,将使用操 作系统的默认设置。
Syntax
无符号整数
Tips
[注意] 不要过度调整这个限制。如果您的应用程序需要更多的内存, 这可能会导致503错误。
内存硬限制⇑
Description
与内存软限制非常相同,但是在一个用户进程中,软限制 可以被放宽到硬限制的数值。硬限制可以在服务器级别或独立的外部应用程序级别设 置。如果未在独立的外部应用程序级别设定限制,将使用服务器级别的限制。
如果在两个级别都没有设置该限制,或者限制值设为0,将使用操 作系统的默认设置。
Syntax
无符号整数
Example
进程软限制⇑
Description
限制一个用户可以创建的进程总数。所有存在的进程都将被统计在内, 而不是只包括新启动的进程。如果限制被设置为10,并且一个用户下 有超过10个进程在运行,那么网站服务器将不会再为该用户(通过 suEXEC) 启动新进程。
此限制的主要目的是为了防范“fork炸弹”攻击或过量使用,而不是限制正常使用 (如果该限制被设置的过低,它将被服务器忽略)。确保留有足够空余。 本项目可以在服务器级别或独立的外部应用程序级别设置。如果未在独立的外部应用程 序级别设定限制,将使用服务器级别的限制。如果在两个级别都没有设置该限制, 或者限制值设为0,将使用操作系统的默认设置。
Syntax
无符号整数
Tips
PHP scripts can call for forking processes. The main purpose of this limit is as a last line of defense to prevent fork bombs and other attacks caused by PHP processes creating other processes.
Setting this setting too low can severely hurt functionality. The setting will thus be ignored below certain levels.
When using suEXEC Daemon mode, the actual process limit will be higher than this setting to make sure parent processes are not limited.