bdgranger commented on issue #8417: URL: https://github.com/apache/trafficserver/issues/8417#issuecomment-942653673
Upon further review of the logs and upon code inspection, we noticed a change that was introduced with PR #6686 that removed the call to remove_trigger_pending_dns() from the dnsEvent method in the case of EVENT_INTERVAL. In this case, if a dns request for an fqdn times out, any "additional requests" that are still in the pending queue will not be removed until their own timers expire. If the request rate to hostdb for that fqdn is high enough (i.e. more frequent than the hostdb timeout), there will always be a request in the pending queue and so the new request will be merged as another "additional request" and no new dns requests for that specific fqdn will be sent down to the dns resolution subsystem. Consulting with Susan Hinrichs on the slack channel, she said: > Yes, looks like your analysis is correct. The schedule_imm only occurs from with the remove_trigger_pending. So we should call remove_trigger_pending in the INTERVAL case but not the IMM case. Should really have some more obvious scheme to note that we are already in the remove_trigger_pending, so we don't have to rely on the specific event types. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
