[Asterisk-bugs] [Asterisk 0010096]: "Maximum PBX stack exceeded" raised by including more than AST_PBX_MAX_STACK *not nested* contexts

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email_notification_title_for_action_bugnote_submitted 
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http://bugs.digium.com/view.php?id=10096 
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Reported By:                AlexB
Assigned To:                
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Project:                    Asterisk
Issue ID:                   10096
Category:                   PBX/General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:            1.2.19  
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        No 
Request Review:              
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Date Submitted:             07-02-2007 04:54 CDT
Last Modified:              07-02-2007 11:56 CDT
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Summary:                    "Maximum PBX stack exceeded" raised by including
more than AST_PBX_MAX_STACK *not nested* contexts
Description: 
Including more than 127 contexts causes
Jul  2 11:16:22 WARNING[5561] pbx.c: Maximum PBX stack exceeded

Please note they are not nested, but just included in one single context.
The value depends by AST_PBX_MAX_STACK, which is set to 128. Anyway this is
supposed to be the maximum depth, not the number of includes.

This behaviour has already been pointed out on the dev mailing list:

http://lists.digium.com/pipermail/asterisk-dev/2007-June/028164.html

There are also other threads opened, but unfortunately the discussion was
not fed by any developer. However this is a bug and plain Asterisk files to
reproduce it are attached.
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 Corydon76 - 07-02-07 11:56  
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Increasing it will certainly affect a measure of performance, as this is a
sequentially searched list and as you increase the number of items in it,
so the time necessary to run the dialplan will increase linearly.

At some point, it may be changed to use a hashtable lookup, which should
change its lookup time from O(n) to O(1), which would be a vast
improvement.  That code, however, is not yet written, so it's a long way
off. 

Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
07-02-07 04:54  AlexB          New Issue                                    
07-02-07 04:54  AlexB          Asterisk Version          =>  1.2.19         
07-02-07 04:54  AlexB          SVN Branch (only for SVN checkou => N/A          
  
07-02-07 04:54  AlexB          Disclaimer on File?       => No              
07-02-07 04:56  AlexB          File Added: extensions.conf                    
07-02-07 04:57  AlexB          File Added: sip.conf                         
07-02-07 10:33  Corydon76      Note Added: 0066403                          
07-02-07 10:52  AlexB          Note Added: 0066410                          
07-02-07 11:28  Corydon76      Note Added: 0066414                          
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