Introduction

The RTPL package ( Remote Throughput, Ping and Load) is a package intended to do periodically net performance measurements tests between a set workstations to obtain the network performance from a user viewpoint. The performance measurements are consisting of roundtrip and throughput measurements between a number of hosts. Default all pairs in the hosts set are used, but it is also possible to select the host pairs for the tests. Also the machine load of the participating workstations is measured. In this way performance lost can be related to heavily machine load.

Because we are interested in the network performance from a user viewpoint and not in the maximum possible capacity of a network, the measurement parameters are configured to default values and the test durations are limited: various long term statistics will blur the short time fluctuations.

The tests are performed by scripts which are written in the generally used scripting language Perl, which is available for many operating systems. The scripts are used to parse, sample and organize the results. The real performance measurements are executed by commonly used Internet tools invoked by the Perl scripts.

The presentation of the results is Web based and dynamic: the net performance data are stored in ZIP compressed plain text files which are accessible from a Web server. There are various files such that a user can be offered several views at the data, including several time based averages. The file data are read into the Web browser of a user by a Java Applet. The HTML scripting language JavaScript is used to display the data in various tables. The Applet can also be used to present the data in plot form.

The RTPL package is only available for Unix platforms. The main reason is that the so called remote shell mechanism, used to obtain the results from the participating hosts, although implemented on Windows NT/9X, is not standard and not generally available. There is also a standard form of the package which only executes roundtrip tests from the local host to a specified set of remote hosts. This basic package is available for both Unix and Windows NT/9X. The basic version is not further discussed in this report.

The roundtrip tests via the ping service is also used by the HEP Internet Monitoring Project (PingER) [1]. This is an initiative to measure the performance of the Internet used by the High Energy Physics Research community. However, we believe that, especially for networks with a larger capacity also throughput measurements are required to become a better overview of the network performance.

This report is organized as follows. Section 2 gives a more detailed description of this package. Also the software to install and the user requirements are discussed here. Section 3 describes some examples of net performance measurements which are currently running. Section 4 contains a proposal for a start setup of a performance test at the TEN-155 network.