1 / 7

Web Application Servers

Web Application Servers. Dean Jacobs BEA WebLogic. The Right Question. Middleware is converging Web Application Servers = TP Monitors What new demands do the Internet and Java place on middleware?. System Architecture. Database. Browsers. Web Servers. Application Server Cluster.

uriah-wright
Télécharger la présentation

Web Application Servers

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Web Application Servers Dean Jacobs BEA WebLogic

  2. The Right Question • Middleware is converging • Web Application Servers = TP Monitors • What new demands do the Internet and Java place on middleware?

  3. System Architecture Database Browsers Web Servers Application Server Cluster

  4. Web Servers • Web Servers not integrated with middleware • Adds an extra server-side hop with no benefit • Obviates the front line of session concentration • Web Servers integrated with middleware • Standard Web Servers must be supported • Front line session handling - load balancing and transactions - must occur in Web Server plug-ins

  5. Relaxed Durability/Consistency • Trade durability or consistency for performance: avoid disk accesses by keeping state in memory. • Shopping Cart Stored as browser-session state in a servlet engine. To avoid writing backups to disk, replicate in-memory on a secondary host. • Catalog Data Changes infrequently and may be briefly out-of-date. To avoid disk reads, cache on many servers in a cluster. Update anywhere and lazily flush the caches.

  6. Fat Processes with Threads • Radically different process model: 2-3 processes per host, each a logical machine • Multiple resource managers per process • Multiple threads accessing each resource • Threads are not isolated from each other

  7. Object Lifetime In-Memory • CORBA relies on the programmer to release objects • Component models (EJB) prescribe object lifetimes • Programming language object models (RMI) require DGC. How can that scale?

More Related