Implement an imperfect cpu_eff correction for nomultithread

slurm-eff-tool.py

@@ -937,6 +937,13 @@ def build_job_records(rows: list[dict[str, str]]) -> list[JobRecord]:
         #       related to 2 hyperthreads, and cputime_raw should have been doubled
         #       for these cases
         cpu_eff = pct(totalcpu, cputime_raw)
+        # We correct for cases where users specify nomultithread, and where
+        # only 1 in 2 CPUs is used. WARNING: This is not perfect!!! Also, we
+        # store this in the cache, so not recalculated from original values
+        # when reading back from cache!
+        if cpu_eff and req_ntasks == alloc_cpus / 2 and cpu_eff <=50:
+            cpu_eff = 2 * cpu_eff
+
         time_eff = pct(elapsed, timelimit_seconds)
 
         # Old metric: