Themis Vassiliadis wrote: > DRCP is really a big improvement. But for me it has a great holdback: > the pool controlled in the server side isn't defined for a specific > schema, so if we have an application server serving different > connections demanding different credentials certainly the performance > will be worse. Another big problem is that one application hosted in the > web server can lock the pool completely is the demand for this > application improve. Pooled servers are internally sub-partitioned by user. See figure 3 in http://www.oracle.com/technology/tech/php/pdf/php-scalability-ha-twp.pdf This allows maximum reuse of pooled users for similar connections. DRCP is perfectly suited for systems with several credentials. I agree that if each and every connection comes in as a separate user then the benefits of DRCP will be reduced. But is conceivable in some cases that you can still take advantage of the already running server processes. > In other hands if we work with traditional pooling, configured in the > client side, we should define one pool for each aplication with his own > credentials. The pool will never blocked by one system and for hosts > with several credentials the performance will be better. The performance > and availability will be insured. The DRCP pool is efficient and doesn't require many servers to handle load. Of course, this is application dependent. The worst case is a temporary shortage of pooled servers. Requests will block until a pooled server is free. But you can set the maximum number of pooled servers as high as your system limitations allow. This ensures the DB is still able to process requests without being totally overloaded. When load does decrease, the pool will shrink. > Of corse both are good solutions, each one for your specific > purpose. I agree that each application & architecture may perform better with one or other solution. If you get a chance to try DRCP, let me know your experience. Chris -- Email: christopher.jones@xxxxxxxxxx Tel: +1 650 506 8630 Twitter: http://twitter.com/ghrd Free PHP Book: http://tinyurl.com/f8jad -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
