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Version: v0.58.0

top_blockio

The top_blockio gadget provides a periodic list of input/output block device activity. This gadget requires Linux Kernel Version 6.5+.

Note: If you have an encrypted disk some block IO operations will not be shown, since device mappers are in between these operations to operate transparently. See https://docs.kernel.org/admin-guide/device-mapper/dm-crypt.html

Requirements​

  • Minimum Kernel Version : 6.6

Getting started​

Running the gadget:

$ kubectl gadget run ghcr.io/inspektor-gadget/gadget/top_blockio:v0.58.0

Guide​

Run a pod / container:

$ kubectl run --restart=Never --image=busybox test-top-blockio -- sh -c 'while true; do dd if=/dev/zero of=/tmp/test count=4096; sync; sleep 0.2; done'
pod/test-top-blockio created

Then, run the gadget and see how it shows the sync process:

$ kubectl gadget run top_blockio:v0.58.0
K8S.NODE            K8S.NAMESPACE       K8S.PODNAME         K8S.CONTAINERNAME          PID        RW  MAJOR      MINOR      COMM       BYTES      US        IO
minikube            default             test-top-blockio    test-top-blockio          8086        wr… 8          0          sync       81920      45        1
minikube            default             test-top-blockio    test-top-blockio          8055        wr… 8          0          sync       606208     547       3
minikube            default             test-top-blockio    test-top-blockio          8082        wr… 8          0          sync       65536      95        2
minikube            default             test-top-blockio    test-top-blockio          8084        wr… 8          0          sync       147456     95        2
...

Finally, clean the system:

$ kubectl delete pod test-top-blockio