3Com S7906E Command Reference Manual page 666

Default Level
2: System level
Parameters
rate: Packet sampling rate, in the range of 1000 to 500000.
Description
Use the sflow sampling-rate command to configure the packet sampling rate.
Use the undo sflow sampling-rate command to restore the default.
By default, the packet sampling rate is 200000, that is, one out of every 200000 packets is sampled.
Note that this command should be used after sFlow is enabled on the current port.
Examples
# Configure the packet sampling rate as 100000 on GigabitEthernet 2/0/1.
<Sysname> system-view
[Sysname] interface GigabitEthernet 2/0/1
[Sysname-GigabitEthernet2/0/1] sflow enable inbound
[Sysname-GigabitEthernet2/0/1] sflow sampling-rate 100000
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