sFlow: Sample size configuration (from 124 to 512 bytes)

You can use the sample-size option to configure the sample size for sFlow packets. The packet size can be up to 512 bytes. The default size of the raw exported header is 128 bytes, which is updated from the current fixed size of 124 bytes. The configured size of the raw packet will be exported to the collector as a part of the flow sample. If the packet size is smaller than the configured sample size, then the complete packet will be sent.