The earliest recollection of this bug is traced back to PAN-OS 8.1.10 - January 09, 2024. This bug is fixed in PAN-OS versions 8.1.10. Fixed an intermittent issue where a large number of packets were received before acknowledgments were complete, which depleted descriptor queue entries and resulted in high latency during data transfers even though CPU usage looked normal. For more information: https://docs.paloaltonetworks.com/pan-os/8-1/pan-os-release-notes/pan-os-8-1-addressed-issues/pan-os-8-1-10-addressed-issues