Request Performance Measurements¶

Added in version 3.3.0

Nautobot can measure the performance of a request.

This is useful for benchmarking, and for determining potential areas of optimization for requests.

Performance measurements are disabled by default.

Settings¶

To enable a performance measurement, change any of these settings to True

Setting	Environment Variable	Measures
`REQUEST_TOTAL_DURATION_HEADER_ENABLED`	`NAUTOBOT_REQUEST_TOTAL_DURATION_HEADER_ENABLED`	Total wall clock time spent processing the request.
`REQUEST_DB_DURATION_HEADER_ENABLED`	`NAUTOBOT_REQUEST_DB_DURATION_HEADER_ENABLED`	Time spent executing SQL during the request, and the number of queries.

Response Headers¶

When a performance measurement is enabled, Nautobot will add a Server-Timing field to the response header. This follows the W3C Server Timing specification.

The Server-Timing header value is a comma-delimited (,) list of performance measurements. Each performance measurement is a semicolon-delimited (;) set of attributes:

name;dur=DURATION;desc="DESCRIPTION"

Name	Description
`name`	Measurement name
`dur`	Measurement duration in milliseconds, rounded to two decimal places
`desc`	Measurement description.

Note

Django Debug Toolbar also reports its timings in the Server-Timing header. If request measurements and Django Debug Toolbar are both enabled, both write to the same header. They do not overwrite each other, but you may see duplicated measurement names.

Measurement Examples¶

Name	Description
`total`	Total request duration.
`db`	Database query duration. The description reports the number of queries.

Example header with both measurements enabled:

Server-Timing: total;dur=33.76;desc="Total request duration", db;dur=4.55;desc="11 database queries"

The header is added to every response, not just API responses. Browsers show it in the network tab of their developer tools.

Curl Example¶

curl --verbose \
     --output /dev/null \
     --header 'Accept: application/json' \
     --header 'Authorization: Token 0123456789abcdef0123456789abcdef01234567' \
     'http://localhost:8080/api/extras/statuses/?limit=1'

< HTTP/1.1 200 OK
< Content-Type: application/json
< API-Version: 3.3
< Content-Length: 1085
< Server-Timing: total;dur=33.76;desc="Total request duration", db;dur=4.55;desc="11 database queries"

Monitoring¶

When a measurement is enabled, its measurements are also exported to Prometheus.

Metrics generated using these measurements are labeled with the requesting user's hashed token. See Prometheus Metrics.