<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On 5 September 2017 at 11:56, Havard Eidnes <span dir="ltr"><<a href="mailto:he@uninett.no" target="_blank">he@uninett.no</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hmm...<br>
<br>
some further local discussion has made me aware that us running<br>
"collectd" for monitoring BIND may be contributing to the<br>
problem; collectd fetches data each 10s by using the BIND-<br>
configured statistics-channel, thus BIND is processing a TCP<br>
connection to deliver the statistics data.<br>
<br>
It's still somewhat surprising and disappointing that this should<br>
interfere this much with DNS query processing...<br><br></blockquote><div>Is that pulling the old-style stats file, or the HTTP-based stats channel? </div><div><br></div><div>If the latter... the zone list (and by extension the root document) seems to take a long time to process, and involves some sort of locking that blocks all query processing while the list is being generated. We encountered this on a 3+ million zone instance.. BIND would stop answering queries for several minutes if anyone requested the root stats document or the zone list.</div><div><br></div><div>As Ray says, you may be better off individually querying each of the other documents and processing those rather than polling the root doc to get them all in one shot.</div></div><br></div></div>