Nicolas Dichtel <[email protected]> wrote:
> After commit b87a2f9199ea ("netfilter: conntrack: add gc worker to remove
> timed-out entries"), netlink conntrack deletion events may be sent with a
> huge delay. It could be interesting to let the user tweak gc parameters
> depending on its use case.
Hmm, care to elaborate?
I am not against doing this but I'd like to hear/read your use case.
The expectation is that in almot all cases eviction will happen from
packet path. The gc worker is jusdt there for case where a busy system
goes idle.
> +nf_conntrack_gc_max_evicts - INTEGER
> + The maximum number of entries to be evicted during a run of gc.
> + This sysctl is only writeable in the initial net namespace.
Hmmm, do you have any advice on sizing this one?
I think a better change might be (instead of adding htis knob) to
resched the gc worker for immediate re-executaion in case the entire
"budget" was used. What do you think?
diff --git a/net/netfilter/nf_conntrack_core.c
b/net/netfilter/nf_conntrack_core.c
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -983,7 +983,7 @@ static void gc_worker(struct work_struct *work)
return;
ratio = scanned ? expired_count * 100 / scanned : 0;
- if (ratio >= 90)
+ if (ratio >= 90 || expired_count == GC_MAX_EVICTS)
next_run = 0;
