My Persistent Disk SSD quota is almost exceeded, despite the fact that I did not fill anything

[Bruce_Q]

Hi!
Could you please help me

Context:
- I created a new project
- I created a auto-pilot GKE cluster
- I launched a super lightweight pod in the cluster
- I launched a gitlab runner in the cluster

Problem:
However, new pods are no longer created - because of the "0/2 nodes are available: 2 Insufficient cpu, 2 Insufficient memory. preemption: 0/2 nodes are available: 2 No preemption victims found for incoming pod" error

In IA&Admin -> Quotas&System Limits i see that "My Persistent Disk SSD" ("service" column value = Compute Engine API) quota is almost exceeded, 200GB/250GB is already in use, despite the fact that I did not fill anything

Debugging:

gcloud compute disks list -> empty

kubectl top nodes -> 

NAME CPU(cores) CPU(%) MEMORY(bytes) MEMORY(%)
<pool-1> 169m 8% 1927Mi 32%
<pool-2> 241m 12% 2508Mi 42%

kubectl describe node <pool-1> ->

Resource Requests Limits
-------- -------- ------
ephemeral-storage 1Gi (2%) 1Gi (2%)

kubectl describe node <pool-2> ->

Resource Requests Limits
-------- -------- ------
ephemeral-storage 0 (0%) 0 (0%)

I'm not new in k8s, but I'm using GCP for the first time

Please tell me how to see what's taking up so much space?