jstack empty contents

Hi,

Facing the below error for some processes,when we are using jstack in jdk-1.8.

18280: Unable to open socket file: target process not responding or HotSpot VM not loaded
The -F option can be used when the target process is not responding

When Tried with -F option also, the Issue was seen. Please let us know how to go about this.

Regards
Shabari