Hol Blocking Prevention; Scheduling Settings; Qos Scheduling - D-Link xStack Reference Manual

xStack® DGS-3120 Series Layer 2 Stackable Managed Switch Web UI Reference Guide
Priority
DSCP
Click the Apply button to accept the changes made.

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:
Use the drop-down menu to select a Priority value. This appears when selecting DSCP
Priority in the DSCP Map drop-down menu.
Enter a DSCP value. This appears when selecting DSCP Priority in the DSCP DSCP
drop-down menu.
Figure 6-10 HOL blocking Prevention window
Description
Click the radio buttons to enable of disable the HOL blocking prevention global
settings.
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