Sun Microsystems x4422a, Руководство пользователя

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Chapter 3 Configuring Driver Parameters 35
Interrupt Parameters
TABLE 3-7
describes the receive interrupt blanking values.
Random Early Drop Parameters
TABLE 3-8
describes the RX random early detection 8-bit vectors, which allows you to
enable random early drop (RED) thresholds. When received packets reach the RED
range packets are dropped according to the preset probability. The probability
should increase when the fifo level increases. Control packets are never dropped and
are not counted in the statistics.
TABLE 3-7
RX Blanking Register for Alias Read
Field Name Values Description
rx_intr_pkts 0 to 511 Interrupt after this number of packets have arrived since
the last packet was serviced. A value of zero indicates no
packet blanking. (Default=3)
rx_intr_time 0 to 524287 Interrupt after 4.5 US ticks have elapsed since the last
packet was serviced. A value of zero indicates no time
blanking. (Default=1250)
TABLE 3-8
RX Random Early Detecting 8-Bit Vectors
Field Name Values Description
red_dv4to6k 0 to 255 Random early detection and packet drop vectors for
when fifo threshold is greater than 4096 bytes and less
than 6,144 bytes. Probability of drop can be
programmed on a 12.5 percent granularity. For
example, if bit 0 is set the first packet out of every eight
will be dropped in this region. (Default=0)