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From Mladen Turk <mt...@apache.org>
Subject Re: Session Affinity after Graceful Apache restart? [was Re: Adding working dynamically with mod_jk status?]
Date Wed, 08 Jun 2005 05:59:13 GMT
William A. Rowe, Jr. wrote:
> At 02:08 PM 6/7/2005, Mladen Turk wrote:
> 
> 
>>It works of course, but IIRC you are planning to use it for
>>reconfiguring mod_jk. I think you might get into the problems
>>with shared memory (particularly on unix) because some child
>>might have a different idea about shared memory addresses.
> 
> 
> Oh - so this is a bug/design flaw in mod_jk?  Does the same
> affect the prefork/worker MPMs?
> 

Actually the WIN32 has no such problems because it uses the
plain memory instead of shared.
Problem with WIN32 is because the closing child and new child
will not share the worker data during restart, so you will loose
the statistics during restart.

With unixes the problem is because the workers are allocated
according to the worker.list and balance_members.
If you change those lists in the config on restart the child
processes could have different shared memory segment addresses.

Like said if you only add to the end of list then everything
will probably be OK.

To resolve that we would actually need a database like shared memory
with worker name as a key.

Regards,
Mladen.

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