Class of Service

On-Chip Buffers (OCB) and External DRAM Buffers

The ACX7000 family of routers have on-chip buffers (OCBs) and external DRAM buffers for virtual output queue (VOQ) buffering. Table 1 shows information about OCB and external DRAM buffers for the ACX7000 family of routers.

Table 1: OCB and External DRAM Buffers for ACX7000 Routers

Platform	Total OCB in MB	Total DRAM Buffer in MB
ACX7024	8	2
ACX7024X	8	2
ACX7100-32C	32	8
ACX7100-48L	32	8
ACX7332	16	4
ACX7348	16	4
ACX7509	64	8

Shared Buffer per VOQ

Shared buffer pool is the unreserved part of the global memory pool that the router dynamically allocates to ports as needed. The ports therefore have shared buffers. Table 2 shows the shared buffer per VOQ based on port speed for ACX7000 routers.

Table 2: Shared Buffer per VOQ for ACX7000 Family of Routers

Interface Speed in Gbps	Shared Buffer per VOQ in MB	Shared Buffer per VOQ in ms
1	5	40
10	50	40
25	250	80
40	250	50
50	250	40
100	500	40
200	500	20
400	500	10

Dedicated Buffer per VOQ

Dedicated buffer pool is the reserved global memory space divided equally among the ports. Each VOQ of a port receives a minimum guaranteed amount of dedicated buffer space not shared among ports. Table 3 shows the default dedicated buffer based on port speed for ACX7000 routers.

Table 3: Dedicated Buffer per VOQ for ACX7000 Routers

Interface Speed in Gbps	Dedicated Buffer per VOQ in KB
1	125
10	125
25	625
40	625
50	625
100	1250
200	2500
400	5000

Configure Shared and Dedicated Buffers

To configure shared and dedicated buffers on the ACX7000 family of routers:

Use the temporal option to configure a shared buffer and use the percent or remainder option to configure a dedicated buffer.