Chelsio Communications Chelsio T4, Installation And User Manual

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Chapter XIV. UDP Segmentation Offload and Pacing
Chelsio T5/T4 Unified Wire for Linux
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Example :
The user wants to transfer UDP data on port 0 of the adapter using the USO engine. The
application has been modified as shown in section 4.1. In order to set a bit rate of 10Mbps for
traffic class 1 with payload size of 1316 on port 0, the following invocation of
cxgbtool is used:
[root@host~]# cxgbtool ethX sched-class params type packet level cl-rl
mode flow rate-unit bits rate-mode absolute channel 0 class 1 max-rate
10000 pkt-size 1316
To get an accurate bit rate per class, data sent by the application to the sockets
should be a multiple of the
value set for the “pkt-size” parameter.
In above example, IO size sent by application should be a multiple of 1316.
Linux Unified Wire currently supports 10240 offload UDP connections. If the
application needs to establish more than 10240 UDP connections, it can check
the return code of ENOSPC from a send() or sendto() call and close this socket
and open a new one that uses the kernel UDP stack.
Note
Note