[Halld-offline] [EXTERNAL] Software versions and simulation issues

[Thomas Britton]

I have been sluggish in adding this in for a variety of reasons. Perhaps we can have a latest approved time stamp per halld-sim?

With “latest” being an option?

Thomas Britton

> On Sep 17, 2019, at 10:37 AM, Sean Dobbs <sdobbs at fsu.edu> wrote:
> 
> Hi all,
> 
> I've been working on tracking down some problems that were reported to me about poor simulation yields which seem to have exposed some issues in how we're dealing with the interaction of software and the CCDB in the current frame work.  Thanks to all who helped in tracking this down.
> 
> The issue started on July 26, when some modifications to the CCDB were made to support changes made to mcsmear to improve the FCAL smearing.  A new halld_sim version was rolled out at this point.  The CCDB changes were not necessarily backward compatible to older halld_im versions, or at least weren't checked - which is fine, that's how our system has been designed so far - but the changes were not announced widely enough, which is a mea culpa,
> 
> For people who were generating simulations themselves, they are usually using the latest CCDB and the straightforward fix is to use the latest version of halld_sim (or a version >= 4.6.0)
> 
> For the centralized submission page, the situation is more problematic.  The default for generating simulations for 2017 data is halld_sim 4.2.0, which is outdated, although there are newer versions that are built.  For other data sets, no up-to-date version of halld_sim exists.  Also, there is no ability in the form to set a CCDB timestamp that would give a version of constants that would work with these older constants.
> 
> So, we should probably discuss this in some more detail in our software meeting this afternoon, and see if there are ways we can improve our defaults and communication to avoid such issues in the future.
> 
> Cheers,
> Sean