discovery: Rename file SD mtime metric
"timestamp" -> "mtime" to be in line with node exporter and clearer.
add unit suffix
@@ -127,7 +127,7 @@ func (t *TimestampCollector) removeDiscoverer(disc *Discovery) {
func NewTimestampCollector() *TimestampCollector {
return &TimestampCollector{
Description: prometheus.NewDesc(
- "prometheus_sd_file_timestamp",
+ "prometheus_sd_file_mtime_seconds",
"Timestamp (mtime) of files read by FileSD. Timestamp is set at read time.",
[]string{"filename"},
nil,
