ngx_http_reqstat_module

Description

This module will help monitor running status of Tengine.

It can provide running status information of Tengine.
The information is divided into different zones, and each zone is independent.
The status information is about connections, requests, response status codes, input and output flows,
rt, upstreams, and so on.
It shows all the results by default, and can be set to show part of them by specifying zones.
It supports for user-defined status by using nginx variables. The maximum of all the status is 50.
It recycles out-of-date running status information.
It supports for defining output format.
It follows the request processing flow, so internal redirect will not affect monitoring.
Do not use variables of response as a condition, eg., $status.

Compilation

The module is compiled into Tengine by default. It can be disabled with '--without-http_reqstat_module'
configuration parameter, or it can be compiled as a '.so' with '--with-http_reqstat_module=shared'.

If you use this module as a '.so', please make sure it is after 'ngx_http_lua_module'. Please refer to
'nginx -m'.

Example

http {

    req_status_zone server "$host,$server_addr:$server_port" 10M;
    req_status_zone_add_indicator server $limit;

    server {
        location /us {
            req_status_show;
            req_status_show_field req_total $limit;
        }

        set $limit 0;

        if ($arg_limit = '1') {
            set $limit 1;
        }

        req_status server;
    }
}

when you call '/us', you will get the results like this:

www.example.com,127.0.0.1:80,162,6242,1,1,1,0,0,0,0,10,1,10,1....

Each line shows the status infomation of a "$host,$server_addr:$server_port".

Default line format:

kv,bytes_in,bytes_out,conn_total,req_total,http_2xx,http_3xx,http_4xx,http_5xx,http_other_status,rt,ups_req,ups_rt,ups_tries,http_200,http_206,http_302,http_304,http_403,http_404,http_416,http_499,http_500,http_502,http_503,http_504,http_508,http_other_detail_status,http_ups_4xx,http_ups_5xx

kv value of the variable defined by the directive 'req_status_zone'. The maximun key length is configurable, 152B by default, and overlength will be cut off
bytes_in total number of bytes received from client
bytes_out total number of bytes sent to client
conn_total total number of accepted connections
req_total total number of processed requests
http_2xx total number of 2xx requests
http_3xx total number of 3xx requests
http_4xx total number of 4xx requests
http_5xx total number of 5xx requests
http_other_status total number of other requests
rt accumulation or rt
ups_req total number of requests calling for upstream
ups_rt accumulation or upstream rt
ups_tries total number of times calling for upstream
http_200 total number of 200 requests
http_206 total number of 206 requests
http_302 total number of 302 requests
http_304 total number of 304 requests
http_403 total number of 403 requests
http_404 total number of 404 requests
http_416 total number of 416 requests
http_499 total number of 499 requests
http_500 total number of 500 requests
http_502 total number of 502 requests
http_503 total number of 503 requests
http_504 total number of 504 requests
http_508 total number of 508 requests
http_other_detail_status total number of requests of other status codes* http_ups_4xx total number of requests of upstream 4xx
http_ups_5xx total number of requests of upstream 5xx

You can use names in the left column to define output format, with directive 'req_status_show_field'
Some fields will be removed in future, because user-defined status has been supported.

tsar can parse the result and monitor, see also https://github.com/alibaba/tsar

Directives

Syntax: _req_status_zone zone_name value size_
Default: none
Context: http

create shared memory for this module. 'zone_name' is the name of memory block.
'value' defines the key, in which variables can be used.
'size' defines the size of shared memory.

Example:

req_status_zone server "$host,$server_addr:$server_port" 10M;

the memory is 10MB, the key is "$host,$server_addr:$server_port", and the name is "server".

Notice, if you want to use tsar to monitor, you should not use comma in the key.

Syntax: _req_status zone_name1 [zone_name2 [zone_name3 [...]]]_
Default: none
Context: http、srv、loc

Enable monitoring. You can specify multiple zones to monitor.

Syntax: _req_status_show [zone_name1 [zone_name2 [...]]]_
Default: _all the targets defined by 'req_status_zone'_
Context: loc

Display the status information. You can specify zones to display.

Syntax: _req_status_show_field field_name1 [field_name2 [field_name3 [...]]]_>
Default: all the fields, including user defined fields>
Context: loc

Define output format, used with the directive 'req_status_show'. You can use names
to define internal supported fields, see it above. And also you can use variables
to define user defined fields. 'kv' is always the first field in a line.

Syntax: _req_status_zone_add_indecator zone_name $var1 [$var2 [...]]_
Default: none
Context: http

Add user-defined status by using nginx variables. The status will be appended at the end of each line on display.

Syntax: _req_status_zone_key_length zone_name length_
Default: none
Context: http

Define the maximun length of key for a zone. The default is 104.

Syntax: _req_status_zone_recycle zone_name times seconds_
Default: none
Context: http

Define the recycle threshold for a zone. Recycle will be switched on when the shared memory is exhausted,
and will only take effect on imformation whose visit frequency is lower than the setting.
The setting frequency is defined by 'times' and 'seconds', and it is 10r/min by default.

req_status_zone_recycle demo_zone 10 60;

Syntax: req_status_lazy on|off

Default: off

Context: http、srv、loc

req_status_lazy directive is used to control whether the variable in the req_status_zone directive is recalculate during the log phasei. In order to solve some variables (such as the upstream_xxx related variable) as a key scene to get empty value.

The Tengine Web Server

Description

Compilation

Example

Directives