diff --git a/src/cristallina/utils.py b/src/cristallina/utils.py
index c5068d4..926d720 100644
--- a/src/cristallina/utils.py
+++ b/src/cristallina/utils.py
@@ -6,7 +6,7 @@ logger = logging.getLogger()
 import numpy as np
 from sfdata import SFDataFiles, sfdatafile, SFScanInfo, SFProcFile
 from xraydb import material_mu
-from joblib import Parallel, delayed
+from joblib import Parallel, delayed, cpu_count
 
 def scan_info(run_number,base_path=None,small_data=True):
     """Returns SFScanInfo object for a given run number. 
@@ -68,7 +68,7 @@ def print_run_info(
         break
 
 
-def process_run(run_number, rois,detector='JF16T03V01', roi_img=True, calculate =None, only_shots=slice(None), n_jobs=12):
+def process_run(run_number, rois,detector='JF16T03V01', roi_img=True, calculate =None, only_shots=slice(None), n_jobs=cpu_count()):
     """Process rois for a given detector. Save the results small data in the res/small_data/run...
     By default only sum of rois is calculated, [mean,std,img] can be added to the "calculate" optional parameter.
     """