Varnish Lurker is getting slower / Ban lists keeps increasing

[Nils Goroll]

On 29/11/17 14:53, Olivier Hanesse wrote:
> After 4 hours without any requests other than "BAN"

side note: As explained before and as documented since
5d713b2d8a796c6d21c2066d8ef1e0beab690dd4 / Wed Aug 30 15:18:13 2017 +0200, even
with ban_cutoff, we need to work the ban list and evaluate bans until we reach
the cutoff. Any once we reached that, all we ware saving is the evaluation of
the bans, we still need to do the work of nuking objects.

So my guess would be that the bans you are seeing are so expensive to evaluate
that your ban lurker has not even reached the cutoff.

While I certainly do want to understand if the issue you are reporting is due to
a genuine bug or inefficiency, I would recommend to get the issued bans under
control in the first place.

Also, taking traffic from a server with a busy ban lurker will most likely not
help, but rather lead to a longer total time to work all bans: Cache access for
requests tests bans concurrently to the ban lurker.

Nils