general/9075: Apache processes are becoming locked in "W" mode.

[Dylan Neild <dy...@realcafes.com>]

>Number:         9075
>Category:       general
>Synopsis:       Apache processes are becoming locked in "W" mode.
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Wed Dec 12 12:40:05 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     dylan@realcafes.com
>Release:        1.3.22
>Organization:
apache
>Environment:
Solaris 8 - Latest Patch Cluster as of 10/19/2001
Compiler is GCC 2.95.2
Uname -a: SunOS fortissimo 5.8 Generic_108529-10 i86pc i386 i86pc
>Description:
Essentially, a high traffic server running:
Server Version: Apache/1.3.22 (Unix) mod_jk PHP/4.0.6 mod_ssl/2.8.5 OpenSSL/0.9.6b

What is happening is that the system is booted and the web server starts and all _appears_ well. If I watch the /server-status screen, eventually I start to see process after process locked in the "W" mode. These processes normally have an SS of several thousand seconds and usually (but not always) have a "Req" value in the 15000000 range (very high, I know). 

If I manually kill these rogue processes by process ID, they die without complaint and the server carries on it's way. If  I don't kill them, eventually, the server becomes non-responsive as all the processes are locked in "W". 

I am using MOD_JK to talk to Tomcat 4.0 (I know, I know.. but mod_webapp seems a little undercooked to me .. I really need the load balancing of mod_jk for this particular application), and I have noticed that these locked processes are all requests for JSP pages. Perhaps this may help. 
>How-To-Repeat:
No way to repeat that I know if. 
>Fix:
None at all. It seems to get better when I disable lookups in my tomcat process, but the problem does still occur. 

Is there anyway to make Apache deal with this automatically?

Perhaps upgrading compilers? PHP revisions? 
mod_ssl and apache are the latest,.
>Release-Note:
>Audit-Trail:
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