Hol Blocking Prevention; Scheduling Settings; Qos Scheduling - D-Link DGS-3620-28PC-SI Product Manual

xStack® DGS-3620 Series Managed Switch Web UI Reference Guide
NOTE: Traffic Control cannot be implemented on ports that are set for Link Aggregation (Port
Trunking).
NOTE: Ports that are in the Shutdown Forever mode will be seen as Discarding in Spanning Tree
windows and implementations though these ports will still be forwarding BPDUs to the Switch's
CPU.
NOTE: Ports that are in Shutdown Forever mode will be seen as link down in all windows and screens
until the user recovers these ports.
NOTE: The minimum granularity of storm control on a GE port is 1pps.

HOL Blocking Prevention

HOL (Head of Line) Blocking happens when one of the destination ports of a broadcast or multicast packet are
busy. The switch will hold this packet in the buffer while the other destination port will not transmit the packet even
they are not busy.
The HOL Blocking Prevention will ignore the busy port and forward the packet directly to have lower latency and
better performance.
On this page the user can enable or disable HOL Blocking Prevention.
To view the following window, click QoS > HOL Blocking Prevention, as show below:
The fields that can be configured are described below:
Parameter
HOL Blocking
Prevention State
Click the Apply button to accept the changes made.

Scheduling Settings

QoS Scheduling

This window allows the user to configure the way the Switch will map an incoming packet per port based on its
802.1p user priority, to one of the eight available hardware priority queues available on the Switch.
To view this window, click QoS > Scheduling Settings > QoS Scheduling as shown below:
Figure 6-7 HOL blocking Prevention window
Description
Click the radio buttons to enable of disable the HOL blocking prevention global
settings.
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