Memory management in PyQGIS during loop

Question

I have a issue about memory management in PyQGIS during loop.

I'm writing a code where there is a while loop.

During the operatione inside the loop that are almost the same,I noticed that the execution time increases and also the RAM occupation too (from 200MB to 128GB). So I tried to write a simplified test script that always executes the same instructions 10.000 times but I notice once again that the execution time increases and the RAM too.

The test script:

• input1: dots shape (23.000 points)
• input2: lines shape (115.000 lines)
• execution: extracts a point from the points shape (always the
  same)-->buffer of 10.000m around the point-->extraction of the lines in the buffer. Cycle 10.000 times.

Below you can find the code and a graph of the times laps for each cycle.

Can you explain me why time increases even if the instructions for each cycle are always the same?

I assume that the memory is not freed every cycle.

Is there a way to fix and keep the time the same every loop?

    #1A -  spatial index on lines
    alg_params = {
        'INPUT': parameters['inputline']#input lines
    }
    outputs['ASpatialIndexOnLines'] = processing.run('native:createspatialindex', alg_params, context=context, is_child_algorithm=True)
    feedback.setCurrentStep(1)
   
    n_loop=0
    while n_loop<10000: #loop 10.000 times
        start_time=time.time()
        
        # 1 - extract random point
        alg_params = {
            'FIELD': 'k',
            'INPUT': parameters['inputpoints'],#input points
            'OPERATOR': 0,  # =
            'VALUE': 100, #extract always point with k=100
            'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
        }
        outputs['ExtractRandomPoint'] = processing.run('native:extractbyattribute', alg_params, context=context,  is_child_algorithm=True)

        feedback.setCurrentStep(2)
        

        # 2 - Buffer 10000m on random point
        alg_params = {
            'DISSOLVE': False,
            'DISTANCE': 10000,
            'END_CAP_STYLE': 0,  # Arrotondato
            'INPUT': outputs['ExtractRandomPoint']['OUTPUT'],
            'JOIN_STYLE': 0,  # Arrotondato
            'MITER_LIMIT': 2,
            'SEGMENTS': 5,
            'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
        }
        outputs['Buffer10000mOnRandomPoint'] = processing.run('native:buffer', alg_params, context=context,  is_child_algorithm=True)

        feedback.setCurrentStep(3)
        

        # 3 - spatial index on buffer
        alg_params = {
            'INPUT': outputs['Buffer10000mOnRandomPoint']['OUTPUT']
        }
        outputs['SpatialIndexOnBuffer'] = processing.run('native:createspatialindex', alg_params, context=context,  is_child_algorithm=True)

        feedback.setCurrentStep(4)
       

        # 4 - extract lines in buffer
        alg_params = {
            'INPUT': outputs['ASpatialIndexOnLines']['OUTPUT'],
            'INTERSECT': outputs['SpatialIndexOnBuffer']['OUTPUT'],
            'PREDICATE': [0],  # interseca
            'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
        }
        outputs['ExtractLinesInBuffer'] = processing.run('native:extractbylocation', alg_params, context=context,  is_child_algorithm=True)
       
        
        end_time=time.time()
        delta_time=round(end_time-start_time,3)
        feedback.pushInfo('{},{}'.format(delta_time,n_loop)) #write time and loop
        n_loop+=1
        if feedback.isCanceled():
            return {}
        
        
        
    # when loop finish-->out_test, last extraction
    alg_params = {
        'INPUT': outputs['ExtractLinesInBuffer']['OUTPUT'],
        'OUTPUT': parameters['out_test']
    }
    outputs['fixGeometries'] = processing.run('native:fixgeometries', alg_params, context=context, is_child_algorithm=True)    
        
        
    return {}