Syntax: timer_resolution interval; Default: — Context: main Reduces timer resolution in worker processes, thus reducing the number of gettimeofday() system calls made. By default, gettimeofday() is called each time a kernel event is received. With reduced resolution, gettimeofday() is only called once per specified interval. Example: timer_resolution 100ms; Internal implementation of the interval depends on the method used: the EVFILT_TIMER filter if kqueue is used; timer

Syntax: timeout time; Default: timeout 60s; Context: mail, server Sets the timeout that is used before proxying to the backend starts.

Syntax: thread_pool name threads=number [max_queue=number]; Default: thread_pool default threads=32 max_queue=65536; Context: main This directive appeared in version 1.7.11. Defines named thread pools used for multi-threaded reading and sending of files without blocking worker processes. The threads parameter defines the number of threads in the pool. In the event that all threads in the pool are busy, a new task will wait in the queue. The max_queue parameter lim

Syntax: tcp_nopush on | off; Default: tcp_nopush off; Context: http, server, location Enables or disables the use of the TCP_NOPUSH socket option on FreeBSD or the TCP_CORK socket option on Linux. The options are enabled only when sendfile is used. Enabling the option allows sending the response header and the beginning of a file in one packet, on Linux and FreeBSD 4.*; sending a file in full packets.

Syntax: tcp_nodelay on | off; Default: tcp_nodelay on; Context: stream, server This directive appeared in version 1.9.4. Enables or disables the use of the TCP_NODELAY option. The option is enabled for both client and proxied server connections.

Syntax: tcp_nodelay on | off; Default: tcp_nodelay on; Context: http, server, location Enables or disables the use of the TCP_NODELAY option. The option is enabled only when a connection is transitioned into the keep-alive state.

Syntax: sub_filter_once on | off; Default: sub_filter_once on; Context: http, server, location Indicates whether to look for each string to replace once or repeatedly.

Syntax: sub_filter_types mime-type ...; Default: sub_filter_types text/html; Context: http, server, location Enables string replacement in responses with the specified MIME types in addition to “text/html”. The special value “*” matches any MIME type (0.8.29).

Syntax: sub_filter_last_modified on | off; Default: sub_filter_last_modified off; Context: http, server, location This directive appeared in version 1.5.1. Allows preserving the “Last-Modified” header field from the original response during replacement to facilitate response caching. By default, the header field is removed as contents of the response are modified during processing.

Syntax: sub_filter string replacement; Default: — Context: http, server, location Sets a string to replace and a replacement string. The string to replace is matched ignoring the case. The string to replace (1.9.4) and replacement string can contain variables. Several sub_filter directives can be specified on one configuration level (1.9.4). These directives are inherited from the previous level if and only if there are no sub_filter directives defined on the current level.