node/doc/api/tracing.md
Ali Ijaz Sheikh 98d9540dd7 src: use uv_hrtime as tracing timestamp
Override the V8 TracingController to provide uv_hrtime based
timestamps. This allows tracing timestamps to be comparable with
process.hrtime timestamps.

Fixes: https://github.com/nodejs/node/issues/17349
PR-URL: https://github.com/nodejs/node/pull/18196
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Andreas Madsen <amwebdk@gmail.com>
2018-01-24 09:58:28 -08:00

1.0 KiB

Tracing

Trace Event provides a mechanism to centralize tracing information generated by V8, Node core, and userspace code.

Tracing can be enabled by passing the --trace-events-enabled flag when starting a Node.js application.

The set of categories for which traces are recorded can be specified using the --trace-event-categories flag followed by a list of comma separated category names. By default the node, node.async_hooks, and v8 categories are enabled.

node --trace-events-enabled --trace-event-categories v8,node,node.async_hooks server.js

Running Node.js with tracing enabled will produce log files that can be opened in the chrome://tracing tab of Chrome.

Starting with Node 10.0.0, the tracing system uses the same time source as the one used by process.hrtime() however the trace-event timestamps are expressed in microseconds, unlike process.hrtime() which returns nanoseconds.