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Specifying SPF calculation interval 
LSDB changes result in SPF calculations. When the topology changes frequently, a large amount of 
network and router resources are occupied by SPF calculation. You can adjust the SPF calculation 
interval to reduce the impact. 
For a stable network, the minimum interval is used. If network changes become frequent, the SPF 
calculation interval is incremented by the incremental interval × 2
n-2
 for each calculation until the 
maximum interval is reached. The value n is the number of calculation times. 
To configure the SPF calculation interval: 
 
Step  Command  Remarks 
1.  Enter system view. 
system-view 
N/A
 
2.  Enter OSPF view. 
ospf 
[
 
process-id | 
router-id
 
router-id | 
vpn-instance
 
vpn-instance-name ] * 
N/A 
3.  Specify the SPF 
calculation interval. 
spf-schedule-interval 
maximum-interval 
[ minimum-interval 
[ incremental-interval ] ]
 
By default: 
•  The maximum interval is 5 
seconds. 
•  The minimum interval is 50 
milliseconds. 
•  The incremental interval is 200 
milliseconds. 
 
Specifying the LSA arrival interval 
If OSPF receives an LSA that has the same LSA type, LS ID, and router ID as the previously received 
LSA within the LSA arrival interval, OSPF discards the LSA to save bandwidth and route resources. 
To configure the LSA arrival interval: 
 
Step  Command  Remarks 
1.  Enter system view. 
system-view 
N/A
 
2.  Enter OSPF view. 
ospf 
[
 
process-id | 
router-id
 
router-id | 
vpn-instance
 
vpn-instance-name ] *
 
N/A 
3.  Configure the LSA arrival 
interval. 
lsa-arrival-interval
 interval
 
The default setting is 1000 
milliseconds. 
Make sure this interval is smaller 
than or equal to the interval set with 
the
 lsa-generation-interva
l 
command.
 
 
Specifying the LSA generation interval 
Adjust the LSA generation interval to protect network resources and routers from being overwhelmed 
by LSAs at the time of frequent network changes. 
For a stable network, the minimum interval is used. If network changes become frequent, the LSA 
generation interval is incremented by the incremental interval × 2
n-2
 for each generation until the 
maximum interval is reached. The value n is the number of generation times. 
To configure the LSA generation interval: