ClearWay Thread Tweaker plug-in for WebSTAR
Version 1.0. December, 1998.
http://www.clearway.com/ThreadTweaker/

Copyright © 1998 ClearWay Technologies, Inc. All Rights Reserved.
The latest version of this software can always be found at <http://www.clearway.com/ThreadTweaker/>
This software is free.  It may be redistributed unmodified, provided that this document is included.

THIS SOFTWARE IS PROVIDED AS-IS.  CLEARWAY TECHNOLOGIES, INC. (CLEARWAY) MAKES NO CLAIMS AS TO THE SUITABILITY OF THIS SOFTWARE TO ANY TASK. BY USING THIS UNSUPPORTED SOFTWARE, YOU ASSUME FULL RESPONSIBILITY FOR ANY AND ALL INJURIES, DAMAGES, OR LOSSES RESULTING EITHER DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE.  IF YOU DO NOT UNDERSTAND OR ACCEPT THESE TERMS, OR IF THIS WAIVER OF LIABILITY IS NOT VALID OR CANNOT BE ENFORCED IN YOUR LOCATION, YOU MUST NOT USE THIS SOFTWARE.  FOR MORE INFORMATION ON BECOMING A LAWYER, CONSULT THE AMERICAN BAR ASSOCIATION AT <HTTP://WWW.ABANET.ORG/>


What is ClearWay Thread Tweaker?
This free PowerPC-only WebSTAR plug-in performs two functions:
1) it improves WebSTAR performance when using plug-ins that create their own threads of execution, 
     including NetCloak, Tango, FireSite, and many other 'large' commercial third-party plug-ins.
2) it fixes a thread handling bug that is present in WebSTAR 3.0.1 and all older versions (3.0.2 is fixed) and 

If you are running any of these 'large' commercial WebSTAR plug-ins, installing the Thread Tweaker plug-in will keep your server running more smoothly, with fewer stalls, hiccups, or 'dead periods'.

This plug-in has been tested on hundreds of Web servers over a period of many months.
No adverse effects have been reported; nevertheless, this plug-in is unsupported.


Requirements
This plug-in requires a PowerPC processor, MacOS 7.x or 8.x, WebSTAR 1.3.2 or later, and 3K of RAM.

This plug-in is not recommended for Web servers other than WebSTAR.  AppleShare/IP, WebTen, Quid Pro Quo, and other Web servers have completely different thread management systems from WebSTAR.  They may have the same problems, or different ones, or not.  

To install, simply place this plug-in in your WebSTAR plug-ins folder and restart WebSTAR.
To remove, remove this plug-in from your WebSTAR plug-ins folder and restart WebSTAR.


What this plug-in does
This plug-in eliminates the Thread bug from WebSTAR 3.0.1 and older versions of WebSTAR.  Whenever it 'catches' the old thread bug, it simply beeps, avoids the bug, and continues execution.  In pre-3.0.2 versions of WebSTAR you may hear several beeps when you Quit WebSTAR - this is the Thread Tweaker catching the bug and letting your server shut down normally.

This plug-in also helps reduce or eliminate the stalls, hiccups, and dead periods that WebSTAR can have when running 'large' plug-ins such as NetCloak, Tango, or FireSite.


About the Thread performance issue
Under some circumstances when running plug-ins that create their own threads, WebSTAR itself will lock the machine and prevent any thread-switching from happening.  This can cause the whole server to stop all processessing until some of WebSTAR's threads and network connections time out.

Because of the nature of this WebSTAR threading problem, you may see a total server freeze when you try to Quit WebSTAR, or a 'dead period' where the server stops all processing completely.  In the case of a 'dead period', the server may recover after a few minutes, after some internal WebSTAR timeouts.

Because of the way WebSTAR 'normally' runs, this WebSTAR bug probably only shows up one in hundred thousand times for most WebSTAR users.  But if you're running plug-ins that create their own threads (NetCloak, Tango, FireSite, etc.), there's a very much higher chance that you'll be bitten by this problem.


About the (old) Thread bug
WebSTAR 3.0.1 and older versions had a bug in their thread management code that could cause WebSTAR to freeze when you tried to Quit it, and under a few other very rare circumstances.  WebSTAR 3.0.2 and later do not have this bug, but older versions still do.

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About ClearWay Technologies, Inc.
ClearWay Technologies, Inc. is a smart, friendly, helpful company that consitently delivers useful Internet products and supports them with great customer service.  ClearWay was founded in January 1996, is privately held, and currently employs five people building and marketing great Internet products.

Check out our Top "Twenty" Tips for Mac Webmasters!  <http://mac-web-tips.clearway.com/>  

Credits
ClearWay Thread Tweaker was written by Mark Kriegsman based on comments, experiences, and feedback from WebSTAR and FireSite users all over the Internet, and from StarNine's engineering team.