3Com 7700 Configuration Manual page 120

112 C 5: R P
HAPTER OUTING
O
ROTOCOL PERATION
Perform the following configurations in IS-IS view..
Table 73 Set SPF Calculation in Slice
Operation
Set SPF calculation in slice
Restore the default configuration
By default, SPF calculation does not divide into slices but runs to the end once,
which can also be implemented by setting the parameter seconds to 0.
After slice calculation is set, the routes that are not processed once will be
calculated in one second.
Normally, the user is not recommended to modify the default configuration. When
the number of routes is between 150,000 and 200,000, it is recommended to set
the parameter seconds to 1, that is, the duration time for SPF calculation each
time is 1 second.
Setting SPF to Release CPU Actively
To prevent SPF calculation from occupying the system resources for a long time,
which has impact on the response speed of the console, SPF can be set to
automatically release the system CPU resources after processing a certain number
of routes and the unprocessed routes will be calculated in one second.
Perform the following configurations in IS-IS view..
Table 74 Set SPF to Release CPU Actively
Operation
Set the interval for SPF to release CPU actively spf-delay-interval number
Restore the default configuration
By default, the CPU is released once when every 5000 routes are processed by the
SPF of IS-IS.
Setting the SPF Computing Interval
When IS-IS LSDB changes, the router will compute the shortest path again.
However, the immediate calculation upon every change will occupy too many
resources and affect the efficiency of the router. In the case that SPF computing
interval is set, when LSDB changes, SPF algorithm will be run after the SPF interval
times out.
Perform the following configurations in IS-IS view..
Table 75 Set SPF Computing Interval
Operation
Set SPF computing interval
Restore default SPF computing interval
If the level is not specified, it defaults to setting the SPF computing interval of
Level-1.
Command
spf-slice-size seconds
undo spf-slice-size
Command
undo spf-delay-interval
Command
timer spf second [ level-1 | level-2 ]
undo timer spf [ level-1 | level-2 ]