# ResetSession not clearing memory
**URL:** https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975
**Category:** ParaView Support
**Tags:** python
**Created:** [January 13, 2025, 5:48pm UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975 "2025-01-13T17:48:31Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@ihelt](https://discourse.paraview.org/u/ihelt)
#### Post date: [January 13, 2025, 5:48pm UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/1 "2025-01-13T17:48:31Z")
Hello,
I’ve been trying to use the ResetSession() function to clear memory in my paraview script, but that doesn’t seem to be working. Am I misunderstanding how memory is managed in paraview? Should I be using a different function? Delete() or del didn’t help at all either.
Thank you
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [January 14, 2025, 9:30am UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/2 "2025-01-14T09:30:16Z")
How do you check memory usage ? The OS is pretty lazy when it comes to reclaiming freed memory. If it doesnt need it, it will still show up as being used although it is available.
---
### Author:  [@ihelt](https://discourse.paraview.org/u/ihelt)
#### Post date: [January 15, 2025, 9:15pm UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/3 "2025-01-15T21:15:37Z")
I’ve just been using the top command on linux, but the issue comes in when my script eventually crashes due to a lack of memory and I get:
error: exception occurred: Subprocess killed
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [January 16, 2025, 8:54am UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/4 "2025-01-16T08:54:23Z")
> [@ihelt](#):
>
> the issue comes in when my script eventually crashes due to a lack of memory
Do you reset session in your script ?
Please share a demo script to reproduce the issue.
---
### Author:  [@ihelt](https://discourse.paraview.org/u/ihelt)
#### Post date: [January 16, 2025, 2:19pm UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/5 "2025-01-16T14:19:09Z")
I had previously opened an issue here ([Paraview ResetSession causing crashes - #3 by ihelt](https://discourse.paraview.org/t/paraview-resetsession-causing-crashes/15751/3)) about ResetSession() causing a crash which had a similar minimally working example (in case this looks familiar), but the code below creates a new layout, which was a remedy suggested in issue 22831 ([https://gitlab.kitware.com/paraview/paraview/-/issues/22831](https://gitlab.kitware.com/paraview/paraview/-/issues/22831)).
```auto
from paraview.simple import *
import os
class pv:
def __init__ (self,casename):
print('Initializing...')
self.enReader = EnSightReader(registrationName='case1', CaseFileName=casename)
# Create layout: Remedy to ResetSession crashing (Paraview issue 22831)
layout = CreateLayout()
self.renderView = GetActiveViewOrCreate('RenderView')
AssignViewToLayout(view=self.renderView, layout=layout)
def __del__ (self):
print('deleting...')
Delete(self.enReader)
ResetSession()
def makeBlock(self):
print('Making block...')
self.extractBlock = ExtractBlock(registrationName='block', Input=self.enReader)
self.extractBlockDisplay = Show(self.extractBlock, self.renderView, 'UnstructuredGridRepresentation')
self.extractBlock.Selectors = ['booster']
def makePicture(self,picName):
pic_path = './'+picName+'.png'
print('Saving '+picName+'...')
layout = GetLayout()
layout.SetSize(1400,200)
if os.path.exists(pic_path):
os.remove(pic_path)
SaveScreenshot(pic_path, self.renderView, ImageResolution=[1400, 200], OverrideColorPalette='BlackBackground')
def main():
# NOTE: "error: exception occurred: Subprocess killed" is a result of all memory being used by CPU
casename1 = /path/to/file.case'
i = 1
while i < 10:
print('-----------------------------------')
pvi = pv(casename1)
pvi.makeBlock()
pvi.makePicture('pic{0:d}'.format(i))
pvi. __del__ ()
del pvi
print('pv{0:d} done'.format(i))
i = i+1
print('done')
if __name__ == ' __main__':
main()
```
Executing this code gives me the following output:
```auto
user:> pvpython --mesa replicateCrash.py
-----------------------------------
Initializing...
VisRTX 0.1.6, using devices:
0: Quadro P2000 (Total: 5.3 GB, Available: 5.1 GB)
Making block...
Saving pic1...
deleting...
deleting...
pv1 done
-----------------------------------
Initializing...
Making block...
Saving pic2...
deleting...
deleting...
pv2 done
-----------------------------------
Initializing...
Making block...
Saving pic3...
deleting...
deleting...
pv3 done
-----------------------------------
Initializing...
Making block...
error: exception occurred: Subprocess killed
```
where the crash coincides with my memory usage being completely full.
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [January 16, 2025, 2:23pm UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/6 "2025-01-16T14:23:43Z")
Make sure you delete the python handles and call the garbage collector, eg:
```auto
Delete(self.enReader)
ResetSession()
import gc
gc.collect()
```
---
### Author:  [@ihelt](https://discourse.paraview.org/u/ihelt)
#### Post date: [January 16, 2025, 3:08pm UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/7 "2025-01-16T15:08:19Z")
Thank you Mathieu! This seemed to do it:
```auto
import gc
def __del__ (self):
print('deleting...')
Delete(self.enReader)
Delete(self.renderView)
Delete(self.extractBlock)
Delete(self.extractBlockDisplay)
ResetSession()
gc.collect()
```
There still appears to be a bit of residual memory usage even after the destructor is called, but I’m not worried about it for the moment
---
### Author:  [@wascott](https://discourse.paraview.org/u/wascott)
#### Post date: [January 16, 2025, 5:57pm UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/8 "2025-01-16T17:57:21Z")
Shouldn’t ResetSession delete all of these objects? Isn’t this a defect in ResetSession?
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [January 17, 2025, 9:09am UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/9 "2025-01-17T09:09:34Z")
ResetSession is reseting the ParaView session, but It definitely should not cleanup python objects.
That being said, maybe it makes sense to add a ResetSessionAndCleanNameSpace to simple.py ?
---
### Author:  [@wascott](https://discourse.paraview.org/u/wascott)
#### Post date: [January 23, 2025, 1:30am UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/10 "2025-01-23T01:30:54Z")
[https://gitlab.kitware.com/paraview/paraview/-/issues/22858](https://gitlab.kitware.com/paraview/paraview/-/issues/22858)
---
### Author:  [@otaolafr](https://discourse.paraview.org/u/otaolafr)
#### Post date: [November 20, 2025, 6:46am UTC](https://discourse.paraview.org/t/resetsession-not-clearing-memory/15975/11 "2025-11-20T06:46:10Z")
and shoulndt be a middle ground? without resetSession, to only clean the deleted objects?
I suspect that this is what it is supposed to do the Delete(filter) but it is not doing it for me at least, and if I call the ResetSession it will remove the other filters.
TL;DR, if i have a bunch of filters and one is taking a lot of memory, and then i delete one of them and even if i also gc.collect() the ram consomption is still there, and well… if i run ResetSession it will clean up the memory but also (obviously) remove the other filters i would like to keep.