Is it possible (or even a good idea) to remove eXist from Orbeon

Hi,

We use an Orbeon 3.7.1 nightly build from 2009/6/1, and I have been looking into some high heap usage. I have discovered that:
 - Despite using the default eXist configuration (where it states it uses a max of 48Mb+24Mb of heap) the org.exist.storage.BrokerPool is at 220Mb and still growing.
 - eXist is also using a massive 5Gb of HDD space, which is also continuing to grow. I assume that this is because state that is stored there is never cleared. It was mentioned in another post that the way to solve this was to stop Orbeon, delete the files and start it again. This is not an acceptable solution for us; we need to be able to to solve this while Orbeon is running.

So:
 - I understand you use eXist for storing session state, such as instance data, but is it necessary? Can Orbeon be run without eXist, simply storing this information in memory (we don't care about the redundancy eXist provides)? Is a configuration without eXist tested or supported anymore?
 - This may be a question for the eXist people (I will also ask them, but while I'm here...), but do you have any idea why eXist is using so much heap space?
 - Why does eXist endlessly grow on disk? Is this because the data you store is constantly growing without being culled, or is it some eXist malfunction?
 - If it because the data is constantly growing, is there sufficient data in the schema that we could do something like purge all stored instance data more than n weeks old (probably using the exist scheduler functionality).
 - Have any of these problems been fixed in builds later than the one we have?

Thanks,
 - Stefan du Fresne

Sounds like we need to do what these people did: http://n4.nabble.com/SessionListener-disabled-by-default-td43851.html

Stefan,

Absolutely, there was a time where the session listener was not
properly enabled by default. That should help!

Otherwise it's probably not a good idea to remove eXist unless an
alternate storage mechanism is implemented for XForms state storage.

-Erik

On Sun, Feb 7, 2010 at 4:59 PM, SCdF <[hidden email]> wrote:

--
You receive this message as a subscriber of the [hidden email] mailing list.
To unsubscribe: mailto:[hidden email]
For general help: mailto:[hidden email]?subject=help
OW2 mailing lists service home page: http://www.ow2.org/wws

Erik Bruchez wrote

Otherwise it's probably not a good idea to remove eXist unless an
alternate storage mechanism is implemented for XForms state storage.

Are there hooks for us to use our own storage mechanism? Could we, for example, point Orbeon to an Oracle schema instead of the integrated eXist DB?

> Erik Bruchez wrote:
>>
>> Otherwise it's probably not a good idea to remove eXist unless an
>> alternate storage mechanism is implemented for XForms state storage.
>>
>
> Are there hooks for us to use our own storage mechanism? Could we, for
> example, point Orbeon to an Oracle schema instead of the integrated eXist
> DB?

There are no hooks at this point. See the end of this thread:

http://n4.nabble.com/Mysql-td1395395.html

-Erik


--
You receive this message as a subscriber of the [hidden email] mailing list.
To unsubscribe: mailto:[hidden email]
For general help: mailto:[hidden email]?subject=help
OW2 mailing lists service home page: http://www.ow2.org/wws