I did try adding to SOLR_OPTS this: "-Djava.net.preferIPv4Stack=true -Dnetworkaddress.cache.ttl=3600" and they didn't seem to have any effect during the triage.
-Tim On Wed, Mar 22, 2023 at 12:44 PM Tim Casey <[email protected]> wrote: > There are some settings which are common to apply to the JVM. You might > try those first. > If you do a search for JVM java DNS settings it will come up. > > On Wed, Mar 22, 2023 at 7:01 AM Tim Funk <[email protected]> wrote: > > > I ran into an interesting situation today with respect to latency due to > > failed DNS lookups. > > > > THE SETUP > > Using RHEL8, openjdk 11, solr 9.1.1. The solr instance was standalone in > a > > mostly out of the box config. (No SSL, only http) > > > > I had 3 entries in /etc/resolv.conf and the first one in the list was > > "broken". It was timing out on requests. > > > > The situation - When I would issue a query - I'd have upwards of a 5 > second > > pause prior to completion of the request. Which feels like a timeout > being > > hit. For example, while on the server "10.0.0.200" > > curl -v ' > > http://10.0.0.200:8983/solr/mycore/select?q=*:*&fq=locale_s:en-us&rows=1 > ' > > > > I then edited jetty.xml to > > remove "org.eclipse.jetty.server.handler.InetAccessHandler" (since I > wasn't > > using an ACL anyways). From there - results seemed to get a little > better. > > I tended to get instant responses, but occasionally, I'd still see the > > multi-second delay. > > > > I'm not sure how to track down this second piece of latency when DNS > fails. > > Is this an opportunity to also remove these lookups to improve > performance? > > > > > > -Tim > > >
