This document contains information about changes and new features of Helios LanTest 2.0 and describes how to use it.
Overview
--------
Helios LanTest is a tool for testing network server volume and local hard disk performance. It allows to test the following how long it takes to
- create 100 files with a size of 20 KB
- open and close 100 files
- delete 100 files
- write a big file with a size of 3,000 KB or 30,000 KB
- read a big file with a size of 3,000 KB or 30,000 KB
- lock and unlock portions of a file for 4,000 times
- read a directory with 320 files
- send a 3,000 KB or 30,000 KB PostScript image to a LaserWriter or LaserWriter spooler
The size of the test file is set by the "Edit Other Settings" item in the "Edit" menu. Selecting slower networks will result in a 3,000 KB file and faster networks in a 30,000 KB file.
Helios LanTest displays the results on the screen and collects them in a logfile for later use, e.g. in a spreadsheet application. It also recognizes how many LanTest copies are running performance tests concurrently, and therefore allows to determine the server performance under heavy load. To test with multiple computers, save the selected settings to the test volume and start LanTest on the individual computers by double clicking the settings file.
Copyright Notice
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Helios LanTest is copyright 1993-1997 by HELIOS Software GmbH, Hannover, Germany. LanTest can be distributed freely as long as the copyright notice and the program itself is left intact (this includes shareware or public domain CD-ROM collections).
LanTest is not a supported product from HELIOS Software GmbH, although we appreciate bug reports or enhancements requests to support@helios.de. Please check the Helios web page http://www.helios.de for further information about Helios products.
Helios, the Helios logo, EtherShare, PCShare, and LanTest are trademarks of HELIOS Software GmbH, Hannover. Other trademarks are the property of their respective owners. Product specifications are subject to change without notice.
System Requirements
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Helios LanTest 2.0 runs on any Apple Macintosh or compatible computer with System 7 or a newer MacOS. It can test any AFP compatible file server or a local harddisk.
How Helios LanTest works
------------------------
During startup Helios LanTest looks for a file named "LanTest.Set" in the same folder from where it was started, and reads its settings from this file. If this file is not found LanTest uses default settings. If the file "LanTest.Set" is not already opened from another copy of LanTest, it locks this file for writing so that no other copy of LanTest started from the same folder may change settings but the first one.
The copy of Helios LanTest which started first is able to change settings, either save the settings to file "LanTest.Set" or to another user-specified file, and may read files previously saved by LanTest. Any copy of LanTest not finding a file named "LanTest.Set" during startup also allows changing, writing and saving settings to files.
Helios LanTest displays the currently selected test volume, and if "Print xxx KB" is checked the currently selected printer in the status line of its window.
Users may select another test volume by using the "File" menu command "Select Test Volume", and another printer by using the Macintosh chooser in the usual way.
When a test is started by clicking in the "Start"-button, LanTest checks whether the user has selected a local volume and if so displays a warning dialog (because the main purpose of LanTest is to test server volumes). If "Print xxx KB" is checked, LanTest also checks the selected printer, and in case it is not of type LaserWriter, LanTest displays a warning dialog (LanTest is not able to test other printers or spoolers than those of type LaserWriter). LanTest does send a PostScript image to the printer but does not actually print it, so only the transfer of the PostScript data is measured.
Upon starting the test Helios LanTest checks how many other LanTest copies are currently testing the same volume/folder using the same LanTest.Set settings file and displays that number.
Depending on the tests the user has checked, LanTest creates some folders and files in the selected test volume/folder which are named according to the node and network number of the Macintosh where LanTest runs (do NOT delete/rename/move these files/folders while any copy of LanTest is running). You will need to make sure that enough disk space is available on the test volume.
Helios LanTest performs the test cycles depending on the user-specified entry field "Number of Tests". After each test cycle LanTest writes its test results to a logfile "LanTest.Logfile.x.y" named according to the node (x) and network number (y) of the computer where LanTest runs (do NOT delete/rename/move this file while any copy of LanTest is running).
If either the number of test cycles is done or if the user clicked the "Stop"-button, LanTest cleans up all temporary folders and files, this can take a while.
Judging the results
-------------------
When judging the results, it should be remembered that the performance in any network situation is dependent on the type of application (3 MacOS computers copying large TIFF files can fill the entire Ethernet bandwidth whereas 200 MacOS computers is no problem if they are running client/server database applications, for example).
Please note, too, that overall MacOS performance (including network performance) is reduced significantly by each additional INIT or screen saver that you use.
Test data is read from and written to the computer's RAM, so the local hard disk speed is not relevant when testing server volumes.
Furthermore, the unusually small size of AppleTalk data packets (about 600 bytes, compared with up to about 1500 for Ethernet and up to about 8 KB for Token-Ring) results in a physical upper limit to the network performance, regardless of which AppleShare networking media you are using (Ethernet, Token-Ring, FDDI etc.). However, this data packet limitation does not hold true for many of the file access activities between NetDoubler-accelerated clients and servers. Helios implemented Asanté's NetDoubler technology in EtherShare NetDoubler which is integrated by default in EtherShare 2.5 and automatically invoked whenever possible.
AppleScript support
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LanTest can be controlled by AppleScript. In order to control a bunch of test computers remotely, you will have to turn on program linking (allow guest access should be checked) and start LanTest on each of the test machines. All machines should mount the same test volume. You could start LanTest on a remote machine using the following script:
set myapp to choose application with prompt "Select Helios LanTest Application"
if result is not {} then
set myfile to choose file with prompt "Select Helios LanTest Settings File" of type "LNTS"
if result is not {} then
tell myapp
activate
open myfile
StartTest
end tell
end if
end if
Changes from previous Versions
------------------------------
• Helios LanTest 2.0 is now "fat binary" and runs native on PowerPC MacOS machines.
• Added support for AppleScript.
• The size of the test file can now be adjusted to be either small or large.
• Fixed the crash with AppleShare Workstation 3.7.
In 2.0.1:
• The toggle between faster and slower networks did not work on 68K Macs.
