Hi, I might be wrong here, but would it not help him if he used optimistic concurrency for writes to ensure consistency of the data ? raghu
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Alexey Loubyansky Sent: Tuesday, November 18, 2003 10:43 PM To: [EMAIL PROTECTED] Subject: Re: [JBoss-user] CMP2 and loadbalancing In this case, to ensure the consistency of the data you have to lock the data in the database. It means using row-locking, i.e SELECT ... FOR UPDATE. To solve the scalability problem, you could consider a read-mostly pattern with 'Standard CMP 2.x EntityBean with cache invalidation' container. Alwyn Schoeman wrote: > Hi, > > My application environment is the following: > 1) The same application is duplicated on multiple servers. > 2) These servers are loadbalanced by hardware in front of the servers which > basically round-robins between the servers. > 3) All client requests via http are session- and stateless. > 4) Each server has the same CMP2 beans as all the servers, referencing data from > a single shared database. > 5) The number of servers can be large. > 6) No JBoss clustering is used, due to lack of knowledge and perhaps 5 above. > 7) Some CMP2 beans will write/change data to the database. > 8) The main table to which most other beans relate will have about 10-20 Million > records. > > My questions are the following: > > How do > 1) ensure that data across all servers is correct and valid. > 2) ensure that CMP2 works fast and efficient taking 1) into account. > > Can you do 1) only by choosing a commit option that reads from database every > time. If so, will performance suck? > > Also, some people reckon that a way to get rid of the CMP2 problem is by using > something like Toplink from Oracle. I guess it is similar to Hibernate. > > I do not see how this will change anything. Any comments? > > Kind regards, > ------------------------------------------------------- This SF. Net email is sponsored by: GoToMyPC GoToMyPC is the fast, easy and secure way to access your computer from any Web browser or wireless device. Click here to Try it Free! https://www.gotomypc.com/tr/OSDN/AW/Q4_2003/t/g22lp?Target=mm/g22lp.tmpl _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. Does SourceForge.net help you be more productive? Does it help you create better code? SHARE THE LOVE, and help us help YOU! Click Here: http://sourceforge.net/donate/ _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
