You signed in with another tab or window. Reload to refresh your session.You signed out in another tab or window. Reload to refresh your session.You switched accounts on another tab or window. Reload to refresh your session.Dismiss alert
Copy file name to clipboardExpand all lines: content/cumulus-linux-517/Layer-1-and-Switch-Ports/Quality-of-Service/_index.md
+17-16Lines changed: 17 additions & 16 deletions
Display the source diff
Display the rich diff
Original file line number
Diff line number
Diff line change
@@ -718,10 +718,10 @@ small-packet-probability 60
718
718
Lossless headroom based on small packet probability is a Beta feature.
719
719
{{%/notice%}}
720
720
721
-
Cumulus Linux calculates the headroom size for lossless priority groups based on the assumption that all packets are small (64 bytes). On Spectrum-5 and earlier, the switch assumes a 100 percent probability of such packets arriving at line rate.
722
-
<!--On Spectrum-6, the switch assumes a 50 percent probability of such packets arriving at line rate. As a result, the configured headroom is often larger than necessary, as traffic typically consists of a mix of packet sizes.-->
721
+
Cumulus Linux calculates the headroom size for lossless priority groups based on the assumption that all packets are small (64 bytes). On Spectrum-5 and earlier, the switch assumes a 100 percent probability of such packets arriving at line rate. As a result, the configured headroom is often larger than necessary, as traffic typically consists of a mix of packet sizes.
722
+
<!--On Spectrum-6, the switch assumes a 50 percent probability of such packets arriving at line rate.-->
723
723
724
-
To enable more accurate headroom calculations, providing for better buffer allocation and improved shared buffer utilization, you can configure the probability of small packets on ports applied with {{<linkurl="#priority-flow-control-(pfc)"text="priority flow control">}}. Based on the configured small packet probability, `switchd` calculates the headroom reservation required for the lossless priority group.
724
+
To enable more accurate headroom calculations, providing for better buffer allocation and improved shared buffer utilization, you can configure the probability of small packets on ports applied with a {{<linkurl="#priority-flow-control-(pfc)"text="priority flow control profile">}}. Based on the configured small packet probability, `switchd` calculates the headroom reservation required for the lossless priority group.
725
725
726
726
{{< tabs "TabID679 ">}}
727
727
{{< tab "NVUE Commands ">}}
@@ -766,25 +766,26 @@ To show the PFC small packet probability setting for a profile, run the `nv show
766
766
767
767
```
768
768
cumulus@switch:~$ nv show qos pfc default-global
769
-
operational applied pending
770
-
----------------------------------- -------
771
-
cable-length 100
772
-
small-packet-probability 60
773
-
tx enable
774
-
rx enable
775
-
[switch-priority] 3
769
+
operational applied
770
+
----------------------------------- -------
771
+
cable-length 100100
772
+
small-packet-probability 4040
773
+
tx enable enable
774
+
rx enable enable
775
+
[switch-priority] 3 3
776
776
```
777
777
<!--
778
778
To show the link pause small packet probability setting for a profile, run the `nv show qos link-pause <profile-id>` command. To show the link pause small packet probability setting for an interface, run the `nv show interface <interface-id> qos link-pause` command.
779
779
780
780
```
781
781
cumulus@switch:~$ nv show qos link-pause default-global
0 commit comments