Bug 807860

Summary: Apache hang on kernel 2.6.18-308.1.1.el5 with large StartServers and low MaxSpareServers
Product: Red Hat Enterprise Linux 5 Reporter: ryanfox
Component: kernelAssignee: Red Hat Kernel Manager <kernel-mgr>
Status: CLOSED WONTFIX QA Contact: Red Hat Kernel QE team <kernel-qe>
Severity: high Docs Contact:
Priority: unspecified    
Version: 5.8CC: richard.a.karhuse, ryanfox
Target Milestone: rcFlags: pm-rhel: needinfo? (ryanfox)
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2014-06-02 09:05:19 EDT Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---

Description ryanfox 2012-03-28 19:53:10 EDT
Description of problem:
	I am able to reliably reproduce an Apache hang (clients connect and wait forever for response) using these prefork mpm settings and kernel 2.6.18-308.1.1.el5. Booting off an earlier kernel (kernel-2.6.18-274.12.1.el5) allows this to work as expected.


Version-Release number of selected component (if applicable):
RH 5.8
kernel-2.6.18-308.1.1.el5
httpd-2.2.3-63.el5


How reproducible:
always


Steps to Reproduce:
httpd.conf

<IfModule prefork.c>
StartServers 1024
MinSpareServers 5
MaxSpareServers 20
ServerLimit 1024
MaxClients 1024
MaxRequestsPerChild 4000
</IfModule>

apachectl restart
while [ 1 == 1 ]; do curl -s http://localhost -o /dev/null; done


Actual results:
After several minutes, apache stops responding to requests. (Unresponsive state occurs naturally after about 10 minutes, but above curl loop speeds up the process to just a few)


Expected results:
requests are served quickly


Additional info:
Comment 1 Richard Karhuse 2012-05-25 16:13:48 EDT
Seeing the same issue.

CaseID:  00647579 

Also, see bug:  https://bugzilla.redhat.com/show_bug.cgi?id=681578

Some other info from the Net for Apache:  http://bugs.centos.org/view.php?id=5634
Comment 2 RHEL Product and Program Management 2014-03-07 07:42:04 EST
This bug/component is not included in scope for RHEL-5.11.0 which is the last RHEL5 minor release. This Bugzilla will soon be CLOSED as WONTFIX (at the end of RHEL5.11 development phase (Apr 22, 2014)). Please contact your account manager or support representative in case you need to escalate this bug.
Comment 3 RHEL Product and Program Management 2014-06-02 09:05:19 EDT
Thank you for submitting this request for inclusion in Red Hat Enterprise Linux 5. We've carefully evaluated the request, but are unable to include it in RHEL5 stream. If the issue is critical for your business, please provide additional business justification through the appropriate support channels (https://access.redhat.com/site/support).