Red Hat Bugzilla – Bug 64499
bind 9 is unresponsive on high load.
Last modified: 2016-10-10 10:09:40 EDT
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Description of problem:
When operating bind9 as a caching name server on a network where there are
thousands of concurrent requests, bind9 shipped with RH7.2 gets unresponsive
without utilizing all system resources (network, CPU, Memory).
I have confirmed this in a lab.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
Send a few thousand concurrent requests to bind9.
Actual Results: bind responds to very few requests, network and CPU are
alsmost completely idle, there is plenty of free RAM, UDP reveice queue fills
up completely (65k).
Expected Results: Consume all available system resources, then fill the UDP
queue and loose requests.
I have sent this request to bind9 mailing list and received an answer that I
should compile bind9 without threads. Read it at:
I have confirmed that by re-compiling bind9 without threads the problem does
not exist: bind9 consumes all available system resources before filling up the
UDP receive queue and loosing requests.
We believe that the new thread libraries might fix this. Could you attempt it
using one of the 8.1 betas?