Veritas Storage Foundation 5.1 SP1 for Oracle RAC Administrator"s Guide (5900-1512, April 2011)

Table 5-4
LLT flow control tunable parameters (continued)
Dependency with other
LLT tunable parameters
When to changeDefaultDescriptionLLT
parameter
Not applicableFor performance reasons, its
value should be either 0 or at
least 32.
32This flow control value
should not be higher than the
difference between the
highwater flow control value
and the lowwater flow
control value.
linkburst
Not applicableDo not change this value for
performance reasons.
Increasing the value can
result in unnecessary
retransmissions.
10LLT sends acknowledgement
of a packet by piggybacking
an ACK packet on the next
outbound data packet to the
sender node. If there are no
data packets on which to
piggyback the ACK packet,
LLT waits for ackval number
of packets before sending an
explicit ACK to the sender.
ackval
Its value should be lower
than that of window. Its
value should be close to the
value of window tunable.
For performance reason, its
value should be changed
whenever the value of the
window tunable is changed
as per the formula given
below: sws = window *4/5.
40To avoid Silly Window
Syndrome, LLT transmits
more packets only when the
count of un-acked packet
goes to below of this tunable
value.
sws
About LMX tunable parameters
The section describes the LMX tunable parameters and how to reconfigure the
LMX module.
LMX tunable parameters
Table 5-5 describes the LMX driver tunable parameters.
Tunable parameters
About LMX tunable parameters
258