default or selected kernelversion does not have config value CONFIG_IP_FIB_TRIE.
Result is shown for kernelversion 5.4.69
FIB_TRIE
modulename: fib_trie.ko
configname: CONFIG_IP_FIB_TRIE
Choose IP: FIB lookup algorithm (choose FIB_HASH if unsure)
└─>FIB_TRIE
In linux kernel since version 2.6.13 (release Date: 2005-08-28)
Use new experimental LC-trie as FIB lookup algorithm.
This improves lookup performance if you have a large
number of routes.
LC-trie is a longest matching prefix lookup algorithm which
performs better than FIB_HASH for large routing tables.
But, it consumes more memory and is more complex.
LC-trie is described in:
IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
IEEE Journal on Selected Areas in Communications, 17(6):1083-1092,
June 1999
An experimental study of compression methods for dynamic tries
Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
<http://www.csc.kth.se/~snilsson/software/dyntrie2/>
This improves lookup performance if you have a large
number of routes.
LC-trie is a longest matching prefix lookup algorithm which
performs better than FIB_HASH for large routing tables.
But, it consumes more memory and is more complex.
LC-trie is described in:
IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson
IEEE Journal on Selected Areas in Communications, 17(6):1083-1092,
June 1999
An experimental study of compression methods for dynamic tries
Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002.
<http://www.csc.kth.se/~snilsson/software/dyntrie2/>