Bug 64499

Summary:	bind 9 is unresponsive on high load.
Product:	[Retired] Red Hat Linux	Reporter:	Costa Tsaousis <costa>
Component:	bind	Assignee:	Daniel Walsh <dwalsh>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Ben Levenson <benl>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	7.2
Target Milestone:	---
Target Release:	---
Hardware:	i686
OS:	Linux
URL:	http://marc.theaimsgroup.com/?l=bind9-users&m=101409787119698&w=2
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2003-01-16 20:59:07 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Costa Tsaousis 2002-05-06 21:00:48 UTC

From Bugzilla Helper:
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; Q312461; .NET 
CLR 1.0.3705)

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):
9.1.3-4

How reproducible:
Always

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.

Additional info:
I have sent this request to bind9 mailing list and received an answer that I 
should compile bind9 without threads. Read it at:
http://marc.theaimsgroup.com/?l=bind9-users&m=101409787119698&w=2

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.

Comment 1 Daniel Walsh 2003-01-16 20:59:07 UTC

We believe that the new thread libraries might fix this.  Could you attempt it
using one of the 8.1 betas?