UX-Bridge Technical Datasheet

e-Spirit AG

FirstSpirit Version 5.x

Table of Contents

1. Introduction

This technical datasheet only applies to the current release of UX-Bridge Release Version 1.6.7.

In Chapter System requirements, it describes the components required for operating the UX-Bridge module. The notes provided on Sizing are derived from the Results of the load test.

2. System requirements

2.1. FirstSpirit

The UX-Bridge module was developed and tested on FirstSpirit 5.2. Up to and including version 1.6.5 the UX-Bridge is compatible with FirstSpirit 4.2R4, however, with the following exception:

  • In FirstSpirit 4.2R4, UX-Bus cannot be run on the internal Jetty server of the FirstSpirit server. More information about installing UX-Bus on a FirstSpirit server can be found in the UX-Bridge installation manual.

System requirements for installing FirstSpirit can be taken from the Technical datasheet for FirstSpirit.

2.2. UX-Bus

The system has to meet the following requirements in order to operate the UX-Bus.

2.2.1. Hardware

  • 100 MB of free hard drive space.
    Depending on the configuration (persistence) and operation (master/slave), significantly more disk space may be needed.
  • 2GB of RAM

2.2.2. Operating system

  • Any platform with a corresponding Java

2.2.3. Java environment

  • Oracle Java 1.7

3. Sizing

The minimum requirements listed above should be sufficient for all scenarios in which the UX-Bus is primarily used for writing the data from FirstSpirit into one or more content repositories. One such use case was tested as part of the load tests. The results can be found in the next chapter.

If the UX-Bus is to serve as a central message component within the website infrastructure, then more resources may be needed. This may apply to scenarios in which one message is sent to the UX-Bus per web application request, for example, to analyze user behavior. You can find details on scaling the UX-Bus in the UX-Bridge installation manual. For such scenarios, a corresponding load test should always be carried out within the project in order to ensure that the requirements for performance and scalability are also met.

4. Results of the load test

Load tests were conducted as part of developing UX-Bridge. The objective was to develop a scenario as realistic as possible that simulates a specific use of UX-Bridge as part of a website that contains both dynamic and pre-generated content.

4.1. Test scenario

4.1.1. Editing system

The scenario operates on the basis that 100 editors are working on the FirstSpirit Client simultaneously. In the process, 1,000 changes are created in the system per day (new contents or editing existing contents). In addition, there is an automatic content import mechanism, which also generates 1,000 changes per day. All changes are released and deployed via a workflow. Generation includes pre-generated HTML files that update the necessary assets (graphics, CSS, JS) and the messages required for updating the files in the content repository.

4.1.2. Website

The project developed in the News scenario tutorial was used as the website. Details on this can be found in the UX-Bridge documentation for developers. This is a hybrid Internet presence with dynamic and pre-generated parts. The news area makes use of a dynamic web application that shows the current press releases to the user and enables dynamic filtering by categories. The remaining pages contain pre-generated HTML.

It is assumed that the dynamic web application accounts for 30% of the page views. The remaining 70% are views of pre-generated pages. This appears to be realistic, because the actual press release is a pre-generated page, and only the overview of the press release is delivered dynamically.

In order to model user behavior as precisely as possible, the test scenarios contain corresponding think times. These were extrapolated from real web surfing behavior. The length of time spent on a page varies between 1 to 4 seconds.

A simulated user always surfs multiple pages per visit. During a visit, a browser cache is simulated so that design elements, JavaScript, and CSS do not have to be requested again. In order to simulate browser behavior, a maximum of 5 simultaneous requests per user are generated to reload resources. The cache is emptied again after ending such a session.

On average, a requested website results in 44 HTTP requests with an average transfer volume of 180 KB. If the files are in the browser cache, the transfer volume is reduced to 25 KB on average.

Up to 5,000 simultaneous users on the website are simulated during the test. The content modifications by the editing system are made during the test at the same time as the load tests on the web server.

4.2. Test infrastructure

In order to be able to scale the number of users easily, the entire test was conducted on Amazon Cloud infrastructure. In doing so, all components were purposely installed on dedicated instances to be able to identify any bottlenecks more easily.

You can find details on Amazon EC2 instance types, visit http://aws.amazon.com/de/ec2/instance-types/. You will also find information there about which hardware roughly corresponds to the instances. An EC2 compute unit offers CPU capacity equivalent to a 1.0-1.2 GHz Opteron or Xeon processor from 2007.

The participating systems were:

FirstSpirit server
m1.small with FirstSpirit
m1.small with ActiveMQ 5.6.0
Web server
m2.4xlarge with nginx 1.0.15
Tomcat for web application
Tomcat for adapter
jMeter (for user simulation)
MySQL for FirstSpirit content sources
Amazon RDS instance of type db.m1.small with MySQL 5.1.61
MySQL instance as content repository
Amazon RDS instance of type db.m1.small with MySQL 5.1.61

Each system (except for the jMeter instances for the client simulation) was present only once; in other words, no clustering of any kind has been carried out yet to improve performance here.

The web server was configured as a proxy for Tomcat. Since the dynamic web application does not deliver any personalized contents, the web server can cache the contents gained from Tomcat for a maximum of one minute. If the editing system modifies content during this time, the cache is invalidated beforehand accordingly, so that the modification immediately becomes visible on the website.

The number of website visitors was increased to 5,000 simultaneous users in a ramp-up phase lasting 30 minutes. This load was maintained for 1 hour and followed by a ramp-down phase lasting 10 minutes. There were no ramp-up or ramp-down phases for content modifications in the editing system. Contents were created constantly and then a deployment was carried out in this case.

All relevant measurement data was acquired by a number of tools and centrally collected and visualized in a Graphite instance (see http://graphite.wikidot.com/).