[Zope] Re: zope on red hat 9 randomly stops functioning

Thomas M G Bennett bennettt@pm.appstate.edu
Tue, 13 May 2003 09:40:04 -0400


Having a similar problem, Zope started and froze shortly after accessing it with a browser,  
and the fix worked,

 I had to investigate "what does this really fix" and found that the fix basically works 
around two components which appear to be directly related to each other.  The first item 
is this fix forces glibc to use a deprecated stack model not the floating stack feature. And 
second, in RedHat at least, the Native Posix Threading Library is forced to use old 
LinuxThreads.  This seems to have been a problem in RedHat since 7 beta, I believe, 
and it is also being seen in other Linux distributions especially with using databases such 
as Oracle, DB2, etc.  It is possibly causing problems on multiple processor machines, I'm 
not certain of that but one report indicated the problem was with the smp kernel which I 
am also using.

I haven't been able to keep up with all the changes in recent versions of Python but has 
the stacks/threading libraries been rewritten?


What I found on the WEB at different sites including bugzilla.RedHat.com [my comments 
in brackets]

Some ... [applications] ... don`t work with the new floating stack feature of the i686 
version of glibc ... you may force glibc to use the deprecated stack model by setting the 
following environment variable:
 LD_ASSUME_KERNEL=2.2.5


Red Hat 7.1 enabled a floating stack feature in the glibc library that breaks the IBM JDK 
1.1.8 [among other things]


rpm: There is a known issue with rpm-4.2-0.69 under newer 2.5.x kernels. This is related 
to NPTL stuff and can be avoided by forcing rpm to use old LinuxThreads instead. To do 
this, run rpm like this:
LD_ASSUME_KERNEL=2.2.5 rpm ..

 However, Red Hat kernel does come with NPTL (Native Posix Threading Library) 
support, which works wonders for threads on Linux.  Getting NPTL into a stock 2.4 
kernel ... is no trivial task.


We (Red Hat) should really try to resolve this before next release.

------- Additional Comment #2 From Jakub Jelinek on 2001-02-13 07:53 ------- 

This is a buggy JDK (it has hardcoded knowledge about thread stacks being 2MB
in size aligned to that size). We're now discussing what do with that.

------- Additional Comment #3 From Jakub Jelinek on 2001-02-17 04:02 ------- 



[and interestingly enough (when you don't need it)]
Please note that since SuSE 8.1 was released after Maple 8, it is not an officially tested 
and supported platform. However, we have provided the following workaround below 
which has successfully allowed SuSE 8.1 users to install Maple 8: 

Using a text editor, comment out "export LD_ASSUME_KERNEL" found in line 1331 of 
the LinuxInstaller.bin file located in /tmp/maple8cd/Linux/Linux as follows: 

#export LD_ASSUME_KERNEL 


Thomas Bennett

5/12/2003 2:46:43 PM, Anand Hattiangadi <anand.hattiangadi@Sun.COM> wrote:

>
>This worked, thank you!
>-Anand
>
>Felix Ulrich-Oltean wrote:
>
>>Anand Hattiangadi <anand.hattiangadi@Sun.COM> writes:
>>
>>I had the same problems.  There are a few suggestions in the archives
>>of this list.  The one that worked for me was to add the following in
>>my ZOPE_HOME/start script, before the call to "python z2.py":
>>
>>export LD_ASSUME_KERNEL=2.2.5
>>
>>HTH
>>
>>Felix.
>>
>>
>>_______________________________________________
>>Zope maillist  -  Zope@zope.org
>>http://mail.zope.org/mailman/listinfo/zope
>>**   No cross posts or HTML encoding!  **
>>(Related lists - 
>> http://mail.zope.org/mailman/listinfo/zope-announce
>> http://mail.zope.org/mailman/listinfo/zope-dev )
>>  
>>
>
>
>
>
>_______________________________________________
>Zope maillist  -  Zope@zope.org
>http://mail.zope.org/mailman/listinfo/zope
>**   No cross posts or HTML encoding!  **
>(Related lists - 
> http://mail.zope.org/mailman/listinfo/zope-announce
> http://mail.zope.org/mailman/listinfo/zope-dev )
>

-----------------------------------------------------------------
Thomas McMillan Grant Bennett      Appalachian State University
Computer Consultant III            University Library
Voice:  828 262 6587	           FAX:    828 262 2797

"Windows: A 32-bit GUI on top of a 16-bit wrapper around an 8-bit 
interpretation of a 4-bit operating system written by a 2-bit 
company."   -David Simmons