Improve precision of duration field in view-metrics (ocaml#1565)

* Improve precision of metrics timestamp.

* Add change entry.

---------

Co-authored-by: Ulysse <[email protected]>

Author: 2 people

CHANGES.md

@@ -6,6 +6,7 @@
 
 ## Fixes
 
+- Improve precision of collected metrics timestamps. (#1565)
 - Fix hover on method calls not showing the type. (#1553, fixes #1552)
 - Fix error on opening `.mll` files (#1557)
 

ocaml-lsp-server/src/document.ml

@@ -156,10 +156,10 @@ end = struct
     let task =
       match
         Lev_fiber.Thread.task t.thread ~f:(fun () ->
-          let start = Unix.time () in
+          let start = Unix.gettimeofday () in
           let pipeline = make_pipeline () in
           let res = Mpipeline.with_pipeline pipeline (fun () -> f pipeline) in
-          let stop = Unix.time () in
+          let stop = Unix.gettimeofday () in
           res, start, stop)
       with
       | Error `Stopped -> assert false