Reference Guide

The buer usage accounting happens for ingress packets on ingress pools and egress packets on egress pool. You can congure ingress
packets buer accounting per priority-group and egress packet buer accounting per queue level.
Congure ingress buer
Default settings
In the default settings for ingress buers, all trac classes are mapped to the default priority group and the buers are reserved per default
priority group ID 7. All buers are part of the default pool and all ports share buers from the default pool.
The reserved buer size is 9360 bytes for the speed of 10G, 25G, 40G, 50G, and 100G. The supported speed varies for dierent platforms.
The following table lists the maximum buer size for dierent platforms.
Table 13. Maximum buer size
Platforms Max buer size
S4000 12 MB
S6010–ON, S4048–ON 16 MB
S41xx 12 MB
Z9100–ON 16 MB
Default settings for Link-level ow control (LLFC)
The following table lists the LLFC buer settings for the default priority group 7.
Table 14. Default setting for LLFC
Speed 10G 25G 40G 50G 100G
Default reserved buer 45KB 45KB 111KB 111KB 111KB
Default Xo threshold 36KB 36KB 75KB 75KB 75KB
Default Xon threshold 9KB 9KB 36KB 36KB 36KB
Default settings for Priority ow control (PFC)
The following table lists the PFC buer settings per PFC priority group.
Table 15. Default settings for PFC
Speed 10G 25G 40G 50G 100G
Default reserved buer for S4000, S4048–ON, S6010–ON 9KB NA 9KB NA NA
Default reserved buer for S41xx, Z9100–ON 9KB 9KB 18KB 18KB 36KB
Default Xo threshold 36KB 45KB 75KB 91KB 142KB
Default Xon threshold 9KB 9KB 9KB 9KB 9KB
Default dynamic share buer threshold(alpha value) 9KB 9KB 9KB 9KB 9KB
NOTE: The supported speed varies for dierent platforms. After the reserved buers are utilized, each PFC starts consuming
shared buers from the lossless pool with the threshold determined by the alpha value.
Congure priority group buer settings
Quality of service
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