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Entry  06 Jul 2016, Zhe Wang, Suggestion, Frontend crush on high event rate 
    Reply  09 Jul 2016, Zhe Wang, Suggestion, Frontend crush on high event rate 
       Reply  10 Jul 2016, Zhe Wang, Suggestion, Frontend crush on high event rate frontend.c
          Reply  13 Jul 2016, Zhe Wang, Suggestion, Frontend crush on high event rate frontend.c
          Reply  13 Jul 2016, Zhe Wang, Suggestion, Frontend crush on high event rate 
             Reply  13 Jul 2016, Zhe Wang, Suggestion, Frontend crush on high event rate 
                Reply  30 Sep 2016, Konstantin Olchanski, Suggestion, Frontend crush on high event rate 
Message ID: 1207     Entry time: 30 Sep 2016     In reply to: 1188
Author: Konstantin Olchanski 
Topic: Suggestion 
Subject: Frontend crush on high event rate 
> 
> More suggestions from John and my reply.
> 
> > we also don't use the VME back plane - it's just too slow - mixing VME commands to plain modules and digitizer modules is unreliable....
> 
> > We use CAEN fiberoptic version 2 to talk to the digitizers directly, we have upto 12 digitizers, and can use all channels for several hours, and can fill to about 75% 
> of the A3818 bandwidth... 
> 
> So far we are limitted to 30 MB/s, if tested with CAEN examples, for example, the wavedump program by CAEN.
> I think is kind of the limit by IDE hard drive.
> Unfortunately we are still far from that limit, only ~ 1 MB/s now.  :(
>

From writing MIDAS frontends for many years, I am starting to form an opinion that this type of problem is undebuggable
in the current midas frontend framework - it is impossible to separate problems in vendor-supplied libraries and linux kernel modules
from problems with midas (i.e. incorrectly created data banks, too-small event buffers getting full) from problems with
bad interaction (collision over the SIGALARM handlers).

I am pondering on a new scheme for midas frontend writing. Perhaps such a new scheme should have a "no midas" mode where you can
compile and link a midas frontend "without midas", leaving you to debug just your code and the vendor code and their interactions.

K.O.
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