Logging and profiling

The server logs to stdout and, by default, to a rotating file under the data dir. A Go profiler listener is available on demand.

Logging

Key	Default	Description
logging.enabled	true	Write the file log, stdout is always on
logging.dir	<data_dir>/logs	Log directory
logging.default_module	distroface-app	File name without .log
logging.max_size	10	Megabytes per file before rotation
logging.max_backups	5	Rotated files kept
logging.max_age	30	Days a rotated file is kept
logging.compress	true	Gzip rotated files

Lines are queued and written by one goroutine so no request blocks on disk. The queue holds 8192 lines. Overflow is dropped and the drop count is reported inline.

Registry request logging, audit entries and Actions job logs are separate from this file. See Audit and Artifacts and cache.

Profiling

Set DISTROFACE_PPROF_ADDR to an address and the process serves Go runtime profiles on a private listener. Nothing listens without the variable.

DISTROFACE_PPROF_ADDR=127.0.0.1:6060 ./distroface
go tool pprof http://127.0.0.1:6060/debug/pprof/profile?seconds=30

Path	Profile
/debug/pprof/	Index, heap, goroutine, mutex, block, allocs, threadcreate
/debug/pprof/profile	CPU, seconds parameter
/debug/pprof/trace	Execution trace
/debug/pprof/cmdline, /debug/pprof/symbol	Process arguments, symbol lookup

Mutex profiling samples one in five contention events and block profiling samples at 100 microseconds. Profiles expose internals, keep the listener on loopback or behind a firewall. A non loopback bind logs a warning.