Forum OpenACS Q&A: error installing xotcl 1.4

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Posted by Carlos Eduardo Lazarini on
I just finished intalling xotcl using xotcl-1.4.0.tar.gz, xotcl-core-0.41.apm, and xotcl-request-monitor-0.37.apm according to and After I installed XOTcl Core and XOTcl Request Monitor from local, I got a server error, initially:
"Server Error, The requested URL cannot be accessed due to a system error on this server."
After a 2nd installation, the server still doen't work and I get the following error message:

* Main Site »Administration
Server Error
There was a server error processing your request. We apologize.

Take me back where I was (before the error)

::throttle: unable to dispatch method 'postauth'
while executing
"$proc $why"

My packages: Kernel 2.6.16-2-686, Debian, Gnome2.14, tcl8.4, openACS-5.2.3, aolserver40r10.

Any ideas ?

Thanks in advance.

Posted by Hamilton Chua on
Please check that you also have libthread installed and compiled for aolserver.

More info about it here ...

Posted by Stan Kaufman on
Carlos, you should install the latest xotcl-core (0.43) and the latest xotcl-request-monitor (0.38). Both are in cvs HEAD. This type of error shows up when versions of the various packages are out of sync, and Gustaf has been developing things so fast, this is an easy situation to encounter. Use the latest and greatest, and if you still have problems, Gustaf will be back at the end of the week to answer questions and deal with bugs.
Posted by Carlos Eduardo Lazarini on
I did with thread2.6.4 and worked great.
Thanks a lot...
Posted by Carlos Eduardo Lazarini on
After installing thread2.6.4 openACS is back and working great.
Thanks for you help.
Posted by Richard Hamilton on
I have the same problem with the following combinations of versions:

[15/Nov/2008:09:58:12][12358.131079][-default:1-] Warning: /acs-admin/ has no doc(title) set.
[15/Nov/2008:09:58:12][12358.131079][-default:1-] Error: GET
referred by ""
::throttle: unable to dispatch method 'postauth'
while executing
"$proc $why"
[15/Nov/2008:09:58:12][12358.131079][-default:1-] Error: Tcl exception:
wrong # args: should be "trace option ?arg arg ...?"
::throttle ::xotcl::Object->trace
invoked from within

Installed versions are:

Aolserver Libraries

OpenACS Code

xotcl-core 0.98
xotcl-request-monitor 0.42

Posted by Gustaf Neumann on
I have the same combination running on my notebook, this combination works in principle.

To be sure which versions the aolserver sees, please run

Do you see the problem only immediately after the install, or as well after a restart of nsd?

If the latter is true, there are most likely earlier messages in the error log.

Greeting from Valencia!
-gustaf neumann

Posted by Richard Hamilton on
Bingo! Earlier error indeed located.

Yes the problem persists beyond server restart. It renders the server completely unable to return pages presumably because it is a request filter that is failing.

[15/Nov/2008:09:52:42][12341.65541][-default:0-] Error: Error sourcing /web/server/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl:
invalid command name "thread::mutex"
while executing
"thread::mutex create"
(procedure "init" line 26)
::throttle ::xotcl::THREAD->init
::xotcl::THREAD ::xotcl::Class->create
invoked from within
"::xotcl::THREAD create throttle {
#set package_id [::xo::parameter get_package_id_from_package_key \
# -package_key "xotcl-..."
(file "/web/server/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl" line 2)
invoked from within
"source $__file "

Posted by Gustaf Neumann on
This message means that libthread is not correctly installed.

Check the installation steps in

Have you compiled libthread with --with-aolserver? Have you added the ns_param?

Posted by Richard Hamilton on

Thank you very much indeed. I had not done so. In fact I had got up this morning specifically to re-trace my steps with the libthread library because having trawled through the code it seemed the most likely source of trouble. Your feedback saved me hours!!

I installed it and the following things happened:

1) There was an error associated with the ::thread object as before and an undeclared variable 'f'

2) After re-starting the server this error disappeared

3) The server was very much slower in returning pages than before the request monitor had been installed

4) When I selected xotcl-request-monitor from the applications list on the openacs index page, the server seemed to get stuck processing the request and no longer responded to any other requests either.

5) After uninstalling xotcl-request-monitor using the package manager the site returned to its previously brisk behaviour.

I have no idea why this is - perhaps my own omissions - but I thought that I would provide the feedback anyway.

Many Thanks

Posted by Gustaf Neumann on
Not sure, what you mean by the "::thread object". Anyhow, i am not much concerned about error which disappear after restart.

Under normal conditions, one is not able to notice the difference in speed between using the request monitor or not (on my notebook the difference is less than 1ms). Something seems still quite wrong in your setup.