Hi Cedric,
Cédric Talon wrote:
Hi, I am new on this mailing list and so it is my first message.
welcome to this list!
I am working on a project which is using OJB in a distributed
environment. The distributed issue is my problem ! I have read there
are important points to respect in this case.
The first one is to use Sequence Manager. It's ok for me.
The second one is the locking issue. I am using the
LockManagerRemoteImpl. So I think it is ok.
Do you use the ODMG-api implementation?
http://db.apache.org/ojb/docu/guides/odmg-guide.html
Only this implementation supports pessimistic locking by default.
The PB-api
http://db.apache.org/ojb/docu/guides/pb-guide.html
only supports optimistic locking by default.
http://db.apache.org/ojb/docu/guides/lockmanager.html
For best performance I would recommend to use optimistic locking (needs
a 'version' column in the database table) for all concurrent modified
persistence objects.
The last point is the cache issue. And this is the subject of this
mail. Currently I am using ObjectCacheDefaultImpl. I know it is not
suitable for distributed environment. That's why I'd like to use
distributed cache.
Here you can find a short description how the cache works
http://www.mail-archive.com/ojb-user@db.apache.org/msg16075.html
My estimation is that in most cases OJB will benefit more from a fast
DB/DB-cache/network (in combination with a session cache) than from a
distributed cache (except you do a lot of "get object by identity" stuff).
I would recommend to run some load tests with/without distributed cache.
I have heard about OS Cache but it requires a multicast network. It
is not possible in my case. I have heard about JCS too. Has anybody
ever used it?
Sorry, I don't have experience in this.
I don't find information to configure it with OJB. Can
anybody help me ?
If you use OJB 1.0.5rc1 change the object-cache element within your
jdbc-connection-descriptor to
one global cache region:
<object-cache class="JCS">
</object-cache>
a cache region for each class:
<object-cache class="JCSPerClass">
</object-cache>
For version 1.0.4 specifiy the full qualified class name (e.g.
org.apache.ojb.broker.cache.ObjectCacheJCSPerClassImpl).
You can configure the JCS cache via the cache.ccf properties file.
regards,
Armin
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
