Working with Large BGP Tables

Memory Concerns

On current versions of TNSR, IPv4 and IPv6 routes both use the main heap for memory instead of their own heap, and thus are unlikely to require tuning except for when dealing with hundreds of thousands or even millions of routes, depending on the configuration.

The memory allocated for the statistics segment may need tuned depending on the number of routes received, especially in cases where TNSR is configured with multiple worker threads.

For specific advice on tuning these values, see Memory Usage and Tuning.

CPU Usage Concerns

In addition to memory, processing large numbers of routes will also consume significant CPU power.

Maintenance of the FIB (processing incoming route changes) is handled by the main thread. If there are no workers, processing incoming packets will also be handled by the main thread. In order to prevent the two tasks from competing for CPU resources, one or more worker thread can be added.

With multiple worker threads available, the main thread will handle incoming routes while the workers process packets.

See CPU Workers and Affinity for information on configuring additional CPU workers.

Warning

When adding workers, tuning memory values may be required, especially for the statistics segment. See Memory Usage and Tuning for details.