Switching user in jupyter makes /api/metrics slowly

[zenglw06]

When I add some users in jupyter, constantly switching users makes the response of /api/metrics slowly.

Suppose there are two users root and jov, I try the following command,

#  default user is jov, now switch to root
sudo su 

# switch to jov
su jov

# switch to root
sudo su
# switch to jov
su jov
...

before switching users, the response time of /api/metrics is 300ms After switching uses, the response time of /api/metrics is 1600ms.

This is too weird

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[zenglw06]

Supplementary note

If i try 'exit' command in the terminal, the response time of /api/merics return to normal level

[jhgoebbert]

The response time is mainly influenced by the time the following get-function takes:
https://github.com/jupyter-server/jupyter-resource-usage/blob/master/jupyter_resource_usage/api.py#L20

I would assume the time the psutil-calls answer are different depending on how many processes/users are active on the system. This seems not to be an issue of jupyter-resource-usage.