Buffer Pools - Alcatel-Lucent 7210 SAS E OS Quality Of Service Manual

Buffer Pools

Buffer pools cannot be created or destroyed in 7210 SAS. The default pools created are
distributed among various ports.
The 7210 SAS E only supports port egress buffer pools. The egress buffer pools are distributed as
access uplink egress buffer pool and access egress buffer pools. During system initialization, based
on the maximum number of ports to be supported for access and access uplink, the total buffer is
distributed into the access egress buffer pool and the access uplink egress buffer pool. The
distribution of the buffers into access and access uplink egress pools take care of the buffer
requirements at the port level for various queue shaping/scheduling mechanisms and for various
packet sizes varying from 64 bytes to jumbo frames
The access uplink port is allocated more buffer as compared to an access port. The 7210 SAS
device is typically used with traffic received through the access ports being aggregated on the
access uplink ports. Thus the access uplink ports will be mostly congested. By providing
additional buffer capacity to access uplink ports as compared to the access ports more bursty
traffic can be transported over the congested links with improved throughput.
7210 SAS-E OS Quality of Service Guide
QoS Policies
Page 43