Buffer pools are used to manage the packet buffer memory resources used to store packets and absorb bursts received on a queue.
The total amount of available buffers (approximately 64 Mb on the 7210 SAS-K 2F1C2T and 7210 SAS-K 2F6C4T, and approximately 512 Mb on the 7210 SAS-K 3SFP+ 8C) is divided among the five buffer pools listed below. In addition, the following buffers are reserved for system internal use (such as multicast queues):
CBS buffer pool
ingress non-ring MBS pool
egress non-ring MBS pool
ingress ring MBS pool
egress ring MBS pool
CBS buffer pool is used to allocate buffers toward CBS configured for ingress and egress queues on the node and some internal system queues.
The CBS pool allocation is as follows:
On the 7210 SAS-K 2F1C2T, the CBS pool is used to allocate buffers toward CBS configured for ingress and egress queues on access SAPs, and ingress and egress queues on access-uplink ports.
On the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C, the CBS pool is used to allocate buffers toward CBS configured for ingress and egress queues on access SAPs, ingress and egress queues on access-uplink ports, and ingress and egress queues on network ports and hybrid ports.
The MBS pool is divided into four pools as shown above: the ingress and egress non-ring MBS buffer pool and the ingress and egress ring MBS buffer pool. The MBS buffer pools can be over-subscribed.
The ingress and egress non-ring MBS buffer pool is used to allocate buffers toward the MBS configured for ingress queues and egress queues respectively on non-ring ports and non-ring service objects. The ingress and egress ring MBS buffer pool is used to allocate buffers toward the MBS configured for ingress queues and egress queues respectively on ring ports and ring service objects.
Ring ports and non-ring ports, and the corresponding ring and non-ring buffer pool on different platforms, are assigned as follows:
On the 7210 SAS-K 2F1C2T, the access ports are designated as non-ring ports by default; this designation cannot be changed. The ingress non-ring MBS pool is used to allocate buffers toward all ingress queues configured on access SAPs. Similarly, the egress non-ring MBS pool is used to allocate buffers toward all egress queues configured on access SAPs.
On the 7210 SAS-K 2F1C2T, all access-uplink ports are designated as ring ports and the ingress and egress ring MBS buffer pool is used to allocate buffers toward access-uplink port ingress and egress queues, respectively.
On the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C, the access ports are designated as non-ring ports by default; this designation cannot be changed. The ingress non-ring MBS pool is used to allocate buffers toward all ingress queues configured on access SAPs. Similarly, the egress non-ring MBS pool is used to allocate buffers toward all egress queues configured on access SAPs.
On the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C, all network ports and access-uplink ports are designated as ring ports by default; this designation cannot be changed. The ingress and egress ring MBS buffer pool is used to allocate buffers toward network port and access-uplink port ingress queues and network port and access-uplink port egress queues, respectively.
On the 7210 SAS-K 2F6C4T and 7210 SAS-K 3SFP+ 8C, when a hybrid port is configured, the behavior is as follows:
SAPs configured on hybrid ports are designated as non-ring service objects.
Network port IP interfaces configured on hybrid ports are designated as ring service objects.
The amount of memory allocated toward these pools is software-defined and not user-configurable. The show pools port-id system command can be used to display total amount of buffers per pool and the amount of buffers in use per pool.
For the 7210 SAS-K 2F1C2T and 7210 SAS-K 2F6C4T, the values are:
A:dut-i# show pools 1/1/1 system
===============================================================================
Pool Information
===============================================================================
Port : 1/1/1
Application : System
MMU Total : 65536 KB
MMU CBS : 14336 KB MMU CBS In Use : 2240 KB
Ingress Ring : 11776 KB Ingress Ring In Use: 0 KB
Ingress NonRing : 11776 KB Ingress NonRing In*: 0 KB
Egress Ring : 11776 KB Egress Ring In Use : 0 KB
Egress NonRing : 11776 KB Egress NonRing In *: 0 KB
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For the 7210 SAS-K 3SFP+ 8C, the values are:
A:dut-i# show pools 1/1/1 system
===============================================================================
Pool Information
===============================================================================
Port : 1/1/1
Application : System
MMU Total : 524288 KB
MMU CBS : 105472 KB MMU CBS In Use : 2240 KB
Ingress Ring : 102400 KB Ingress Ring In Use: 0 KB
Ingress NonRing : 102400 KB Ingress NonRing In*: 0 KB
Egress Ring : 102400 KB Egress Ring In Use : 0 KB
Egress NonRing : 102400 KB Egress NonRing In *: 0 KB
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