1.3 KiB
Table of Contents
Overview
lnd
ships with a few useful features for debugging, such as a built-in
profiler and tunable logging levels. If you need to submit a bug report
for lnd
, it may be helpful to capture debug logging and performance
data ahead of time.
Debug Logging
You can enable debug logging in lnd
by passing the --debuglevel
flag. For
example, to increase the log level from info
to debug
:
$ lnd --debuglevel=debug
You may also specify logging per-subsystem, like this:
$ lnd --debuglevel=<subsystem>=<level>,<subsystem2>=<level>,...
Capturing pprof data with lnd
lnd
has a built-in feature which allows you to capture profiling data at
runtime using pprof, a profiler for
Go. The profiler has negligible performance overhead during normal operations
(unless you have explicitly enabled CPU profiling).
To enable this ability, start lnd
with the --profile
option using a free port.
$ lnd --profile=9736
Now, with lnd
running, you can use the pprof endpoint on port 9736 to collect
runtime profiling data. You can fetch this data using curl
like so:
$ curl http://localhost:9736/debug/pprof/goroutine?debug=1
...