comment

proto/src/profile.rs

@@ -5,6 +5,7 @@ pub mod pprof {
 }
 
 use anyhow::{anyhow, Result};
+use pprof::Label;
 use std::collections::hash_map::Entry;
 use std::collections::HashMap;
 
@@ -288,6 +289,11 @@ impl Pprof {
             unit: self.get_or_insert_string("nanoseconds"),
         };
 
+        // Used to identify that the profile was generated by lightswitch.
+        // This matters because the mapping ID is used in a non-standard way
+        // which should not be interpreted like this by other profiles.
+        let comments = vec![self.get_or_insert_string("lightswitch")];
+
         pprof::Profile {
             sample_type: vec![sample_type, period_type.clone()],
             sample: self.samples,
@@ -301,7 +307,7 @@ impl Pprof {
             duration_nanos: 0,
             period_type: Some(period_type),
             period: 1_000_000_000 / self.freq_in_hz,
-            comment: vec![],
+            comment: comments,
             default_sample_type: 0,
         }
     }