Record last_trace_cache_stop when miss the cache (Lightning-AI#2675)

Co-authored-by: Thomas Viehmann <[email protected]>
Co-authored-by: KaelanDt <[email protected]>

Author: 3 people

thunder/__init__.py

@@ -729,6 +729,7 @@ def get_computation_and_inputs(*args, **kwargs):
 
                     # Updates cache statistics
                     cs.cache_hits += 1
+                    cs.last_trace_cache_stop = time.perf_counter_ns()
                     cs.last_traces = comp_traces
                     cs.last_interpreted_instructions = None
                     cs.last_interpreter_log = None
@@ -759,6 +760,7 @@ def get_computation_and_inputs(*args, **kwargs):
 
                 # Updates cache statistics
                 cs.cache_hits += 1
+                cs.last_trace_cache_stop = time.perf_counter_ns()
                 cs.last_traces = comp_traces
                 cs.last_interpreted_instructions = None
                 cs.last_interpreter_log = None