NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator's Guide

Introduction to NSJSP
NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator’s Guide—596210-006
1-11
NSJSP Features
NSJSP Features
NSJSP is distinguished by the following key features:

Scalability
Scalability in NSJSP refers to its ability to increase its capacity to process a large
number of servlet and JSP requests simultaneously, by adding resources, such as
additional processes and logical processors, to a system. The request throughput
rate for NSJSP increases in proportion to the increase in system resources, such
as logical processors and the number of cores in multi-core processors. NSJSP is
highly scalable because it uses the highly scalable iTP Secure WebServer as a
front-end and because it runs as a TS/MP server class, it inherits the scalability
features from TS/MP.

Load balancing
With NSJSP, load balancing is achieved through the use of multiple HP NonStop
subsystems, including HP NonStop TCP/IPv6, TS/MP, iTP Secure Webserver, and
NSJSP. Using NonStop TCP/IPv6 ensures that the incoming HTTP requests are
distributed equally across the HTTPD processes running on all the processors.
Also, because HTTPD communicates with NSJSP using server class send calls,
TS/MP link management can help ensure that HTTPD requests for NSJSP
services are balanced across all the available server class processes of NSJSP.

High-availability
High-availability guarantees continuous availability of services even during a failure
of some system resources, such as processors. Because NSJSP is installed as a
TS/MP server class, if there is a processor failure, TS/MP ensures that new
processes are started on processors that are still available. In addition to the high-
availability features provided by TS/MP, NSJSP itself provides features, such as
session persistence to ensure that the state of an application is not lost in the
event of a resource failure.
If NSJSP is installed in an iTP Secure WebServer environment configured for
online-upgrade (that is, the iTP Secure WebServer is configured in two
PATHMONs, within a Pathway domain), you can modify the NSJSP configuration
while maintaining continuous access to all NSJSP applications and services.

iTP Secure WebServer Online-Upgrade
iTP Secure Webserver 7.0 includes the online-upgrade feature, which enables you
to perform modifications to the web server or user applications hosted on the iTP
Secure WebServer at run time. The online-upgrade feature is enabled by installing
the iTP Secure WebServer in a TS/MP Pathway domain environment that includes
two PATHMONs. While applications in processes under one PATHMON are shut
down for an upgrade, user requests will continue to be processed by the
applications running in processes under the other PATHMON.