Flow Cache Maintenance

The size and the number of entries in the flow cache are platform dependent. Table A-1 lists the default values.

Table A.1. Flow Cache Entry Default Values
PlatformDefault Cache EntriesDefault Memory for NetFlow Cache
AS5800, 4x00, 3600, 2600, 2500, 1600, 14004000256 KB
7200, RSP700064,0004 MB
VIP with 16 MB DRAM2000128 KB
VIP with 32 MB DRAM32,0002 MB
VIP with 64 MB DRAM64,0004 MB
VIP with 128 MB DRAM128,0008 MB

Each time a new flow is added to the NetFlow cache, the number of available NetFlow cache entries is checked. If only a few free flows remain, NetFlow attempts to age 30 of the existing flows using an accelerated timeout. If only one free flow remains, NetFlow automatically ages 30 existing flows regardless of their ...

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