From ba2a076001be6e4140fbd2703cd134e5aa51450b Mon Sep 17 00:00:00 2001 From: Ondrej Zajicek Date: Sun, 15 May 2022 15:05:13 +0200 Subject: BGP: Improve tx performance during feed/flush The prefix hash table in BGP used the same hash function as the rtable. When a batch of routes are exported during feed/flush to the BGP, they all have similar hash values, so they are all crowded in a few slots in the BGP prefix table (which is much smaller - around the size of the batch - and uses higher bits from hash values), making it much slower due to excessive collisions. Use a different hash function to avoid this. Also, increase the batch size to fill 4k BGP packets and increase minimum BGP bucket and prefix hash sizes to avoid back and forth resizing during flushes. This leads to order of magnitude faster flushes (on my test data). --- nest/rt-table.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'nest') diff --git a/nest/rt-table.c b/nest/rt-table.c index a10979e6..c3563171 100644 --- a/nest/rt-table.c +++ b/nest/rt-table.c @@ -2380,7 +2380,7 @@ static void rt_prune_table(rtable *tab) { struct fib_iterator *fit = &tab->prune_fit; - int limit = 512; + int limit = 2000; struct channel *c; node *n, *x; -- cgit v1.2.3