[mapserver-users] Reloading MapCache configuration file on changes?

[Pavel Iacovlev]

Sorry to come up with this again, Is it possible for mapcache to
reload the apache process gracefully automatically if configuration
changes are detected ?

On Wed, Feb 22, 2012 at 1:16 PM, thomas bonfort <tbonfort at terriscope.fr> wrote:
> kept in memory accross the lifetime of the process. the conf file is
> accessed at each request to check it's modification time though if you
> have enabled auto reloading.
>
> --
> tb
>
> On Wed, Feb 22, 2012 at 12:00, Pavel Iacovlev <iacovlev.pavel at gmail.com> wrote:
>> Thank you for the sudo rule suggestion and for detailed explanation!
>>
>> Just one more question, if I use MapCache as fcgi, does this mean that on
>> every request the configuration will be read and parsed ? or the
>> configuration will be kept in memory until a the fastcgi process killed
>> and respawned ?
>>
>>
>> On Wed, Feb 22, 2012 at 12:37 PM, thomas bonfort <tbonfort at terriscope.fr>
>> wrote:
>>>
>>> On Wed, Feb 22, 2012 at 11:22, Pavel Iacovlev <iacovlev.pavel at gmail.com>
>>> wrote:
>>> > apache2ctl -k graceful is not really an option for me because I would
>>> > have
>>> > to give root privileges to my apache/php.
>>> you can create a sudo rule that only allows a user to run apache2ctl
>>> -k graceful without giving full root access.
>>>
>>> >
>>> > "AFAIK, this isn't possible." I don't know anything about apache modules
>>> > and
>>> > stuff so the next thing I say may not be applicable or just plain
>>> > stupid,
>>> > but maybe each process will hold their own copy of configuration so the
>>> > apache process will be able to alter it's configuration upon detection
>>> > of
>>> > file change. There is certainly that added overhead of "checking last
>>> > modified date" and keeping more copies in memory, but this should not be
>>> > the
>>> > default behavior.
>>>
>>> afaik, at the request level (which is were the freshness test would
>>> occur), there's no way of freeing the memory that allocated the
>>> initial configuration, and no way of allocating memory for the new
>>> configuration that would live across the upcoming requests.
>>>
>>> >
>>> > On Tue, Dec 6, 2011 at 1:00 PM, thomas bonfort <tbonfort at terriscope.fr>
>>> > wrote:
>>> >>
>>> >> AFAIK, this isn't possible. Inside an apache module, the configuration
>>> >> is considered read-only as it is shared between multiple worker
>>> >> threads/processed spawned by httpd.
>>> >>
>>> >> apachectl configtest && apachectl graceful will restart the server
>>> >> gracefully, i.e. without aborting ongoing requests, and will load the
>>> >> new configuration for subsequent requests.
>>> >>
>>> >> --
>>> >> thomas
>>> >>
>>> >> On Mon, Dec 5, 2011 at 23:37, John Taranu
>>> >> <jtaranu at firstbasesolutions.com> wrote:
>>> >> > Thomas,
>>> >> >
>>> >> >
>>> >> >
>>> >> > Is there a better way force MapCache to reload its configuration
>>> >> > script
>>> >> > than
>>> >> > restarting apache?  I’m working on an application that will use two
>>> >> > load-balanced web servers running MapCache, all pointing to a single
>>> >> > central
>>> >> > tile repository and a single central .xml configuration file.  The
>>> >> > configuration file will occasionally be edited, either with deletions
>>> >> > or
>>> >> > additional tilesets.  Both web servers need to reload the updated
>>> >> > configuration .xml.
>>> >> >
>>> >> >
>>> >> >
>>> >> > Is it possible to set up MapCache to check if the config file was
>>> >> > recently
>>> >> > updated and, if so, reload the config .xml?  It looks like this is
>>> >> > currently
>>> >> > enabled under FastCGI, but not under Apache.
>>> >> >
>>> >> >
>>> >> >
>>> >> > John
>>> >> _______________________________________________
>>> >> mapserver-users mailing list
>>> >> mapserver-users at lists.osgeo.org
>>> >> http://lists.osgeo.org/mailman/listinfo/mapserver-users
>>> >
>>> >
>>
>>