4-6
Add-on Card User's Guide
Parameter
Name
Valid Range/Set-
tings
Default Description
Interrupt-
ThrottleRate
(not supported on
Intel(R) 82542,
82543 or 82544-
based adapters)
Valid Range:
0,1,3,100-100000
(0=off, 1=dynam-
ic, 3=dynamic
conservative)
3
Since 7.3.x, the driver has two adap-
tive modes (setting 1 or 3) in which it
dynamically adjusts the InterruptThrott-
leRate value based on the traffi c that it
receives. After determining the type of
incoming traffi c in the last timeframe, it
will adjust the InterruptThrottleRate to
an appropriate value for that traffi c.
The algorithm classifi es the incoming
traffi c every interval into
classes. Once the class is determined,
the InterruptThrottleRate value is ad-
justed to suit that traffi c type the best.
There are three classes defi ned: “Bulk
traffi c”, for large amounts of packets
of normal size; “Low latency”, for small
amounts of traffi c and/or a signifi cant
percentage of small packets; and
“Lowest latency”, for almost completely
small packets or minimal traffi c.
In dynamic conservative mode, the In-
terruptThrottleRate value is set to 4000
for traffi c that falls in class “Bulk traffi c”.
If traffi c falls in the “Low latency” or
“Lowest latency” class, the Interrupt-
ThrottleRate is increased stepwise to
20000. This default mode is suitable for
most applications.
See Note at the end of this table for
more information
