Web application servers
1 / 7

Web Application Servers - PowerPoint PPT Presentation

  • Uploaded on

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.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' Web Application Servers' - uriah-wright

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Web application servers

Web Application Servers

Dean Jacobs

BEA WebLogic

The right question
The Right Question

  • Middleware is converging

    • Web Application Servers = TP Monitors

  • What new demands do the Internet and Java place on middleware?

System architecture
System Architecture



Web Servers

Application Server Cluster

Web servers
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

Relaxed durability consistency
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    • Catalog Data Changes infrequently and may be briefly out-of-date.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.

Fat processes with threads
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

Object lifetime in memory
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?