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Entry  13 Jun 2012, Exaos Lee, Bug Report, Cannot start/stop run through mhttpd 
    Reply  13 Jun 2012, Konstantin Olchanski, Bug Report, Cannot start/stop run through mhttpd 
       Reply  13 Jun 2012, Exaos Lee, Bug Report, Cannot start/stop run through mhttpd 
       Reply  14 Jun 2012, Exaos Lee, Bug Report, Cannot start/stop run through mhttpd 
          Reply  14 Jun 2012, Stefan Ritt, Bug Report, Cannot start/stop run through mhttpd 
             Reply  14 Jun 2012, Konstantin Olchanski, Bug Report, Cannot start/stop run through mhttpd 
                Reply  21 Jun 2012, Stefan Ritt, Bug Report, Cannot start/stop run through mhttpd 
          Reply  14 Jun 2012, Konstantin Olchanski, Bug Report, Cannot start/stop run through mhttpd 
Message ID: 808     Entry time: 21 Jun 2012     In reply to: 800
Author: Stefan Ritt 
Topic: Bug Report 
Subject: Cannot start/stop run through mhttpd 
> I agree. Somehow mhttpd cannot run mtransition. I am not super happy with this dependance on user $PATH settings and the inability to capture error messages 
> from attempts to start mtransition. I am now thinking in the direction of running mtransition code by forking. But remember that mlogger and the event builder also
> have to use mtransition to stop runs (otherwise they can dead-lock). So an mhttpd-only solution is not good enough...

The way to go is to make cm_transition multi-threaded. Like on thread for each client to be contacted. This way the transition can go in parallel when there are many frontend computers for example, which will speed up 
transitions significantly. In addition, cm_transition should execute a callback whenever a client succeeded or failed, so to give immediate feedback to the user. I think of something like implementing WebSockets in mhttpd for that (http://en.wikipedia.org/wiki/WebSocket).

I have this in mind since many years, but did not have time to implement it yet. Maybe on my next visit to TRIUMF?

Stefan
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