Use realized data in benchmarks when requested (SciTools#6339)

* Use realized data in benchmarks when requested

* Add whatsnew

Author: bouweandela

benchmarks/benchmarks/generate_data/__init__.py

@@ -106,11 +106,14 @@ def load_realised():
     file loading, but some benchmarks are only meaningful if starting with real
     arrays.
     """
+    from iris.fileformats._nc_load_rules import helpers
     from iris.fileformats.netcdf.loader import _get_cf_var_data as pre_patched
 
     def patched(cf_var, filename):
         return as_concrete_data(pre_patched(cf_var, filename))
 
-    netcdf._get_cf_var_data = patched
-    yield netcdf
-    netcdf._get_cf_var_data = pre_patched
+    netcdf.loader._get_cf_var_data = patched
+    helpers._get_cf_var_data = patched
+    yield
+    netcdf.loader._get_cf_var_data = pre_patched
+    helpers._get_cf_var_data = pre_patched

benchmarks/benchmarks/generate_data/stock.py

@@ -162,7 +162,8 @@ def realistic_4d_w_everything(w_mesh=False, lazy=False) -> iris.cube.Cube:
     lazy : bool
         If True, the Cube will be returned with all arrays as they would
         normally be loaded from file (i.e. most will still be lazy Dask
-        arrays). If False, all arrays will be realised NumPy arrays.
+        arrays). If False, all arrays (except derived coordinates) will be
+        realised NumPy arrays.
 
     """
 

docs/src/whatsnew/latest.rst

@@ -145,6 +145,9 @@ This document explains the changes made to Iris for this release
 #. `@trexfeathers`_ temporarily pinned Sphinx to `<8.2`.
    (:pull:`6344`, :issue:`6345`)
 
+#. `@bouweandela`_ fixed a bug in the benchmarking code that caused all benchmarks
+    to be run with lazy data. (:pull:`6339`)
+
 
 .. comment
     Whatsnew author names (@github name) in alphabetical order. Note that,