Kyle Brown, IBM Fellow, CTO for the IBM CIO Office, Author of Cloud Application Architecture Patterns, The Cloud Adoption Playbook, and many more. See my homepage at http://www.kyle-brown.com/ for the latest updates.
Originally posted by Son Java:
Kyle,
Thanks for your reply.
1) I read the EJB spec for Commit Options. We are currently using Websphere3.5 (and planning to migrate to WAS4 in near future). What is the option is implemented in WAS3.5? Is this option implemented by the container provider or it can be modified from option A to B or C by the App server adminstartor during deployment? How do we set the option in App Server?
2)In our application, we do not go thru entity bean for Read Only data. We directly call the Database from session Bean via prepared statements. What kind of caching can be implemented for the Read Only data from Session Beans.
Thanks
Kyle Brown, IBM Fellow, CTO for the IBM CIO Office, Author of Cloud Application Architecture Patterns, The Cloud Adoption Playbook, and many more. See my homepage at http://www.kyle-brown.com/ for the latest updates.
Originally posted by Son Java:
Kyle,
Assuming that the container implements Option A or Option B and in the scenario of concurrent access from multiple transaction,
CASE 1: Does ejbLoad()acquires an exclusive lock on the instances' state in the database
(OR)
CASE 2: Does ejbLoad() acquire a shared lock and the instance is updated, then ejbStore() will need to promote the lock to an exclusive lock.
As per CASE 1, throughput of read-only transaction could be impacted
As per CASE 2, tt may cause deadlock if concurrently under multiple transactions.
In our application, during concurrent access from multiple transaction, We get 8177 - Can't Serialize Exception. We are using Oracle Database.
If WAS3.5 impelemnets Option A or B, is it possible to decide to go with CASE 1. I am afraid we get Can't Serialize Exception due to the CASE 2 situation.
And All our Entity Beans are BMP with CMT with TX_ATTRIBUTE: TX_REQUIRED and Isolation LEvel as Tx_Serializable.
Thanks
Kyle Brown, IBM Fellow, CTO for the IBM CIO Office, Author of Cloud Application Architecture Patterns, The Cloud Adoption Playbook, and many more. See my homepage at http://www.kyle-brown.com/ for the latest updates.
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