[Halld-offline] Transition to JANA2

[Alexander Austregesilo]

Dear Colleagues,

After many months of comparisons and bug fixes, we feel confident to 
schedule the transition of the entire GlueX software stack to JANA2 
(jeffersonlab.github.io/JANA2). This directly affects the development of 
the packages halld_recon, halld_sim, and hdgeant4. After the coordinated 
transition, the master branch of these packages will only compile 
against JANA2!

We plan to perform a synchronous merge of the JANA2 branches into the 
respective master branch for halld_recon, halld_sim, and hdgeant4 on 
Tuesday, February 11th. With these, we will release a new version set 
which will become the default version at JLab during the following night.

Big thanks to Raiqa Rasool, who spearheaded this transition process with 
support from David Lawrence and Nathan Brei.

Please raise any concerns you may have about this plan.

Best regards,

Alex


==================

Additional resources


If you want to try it out before the big switch, please use 
version_5.22.3_jana2.xml on the ifarm.

The command for the hd_root process will require a small modification:

* J1: hd_root --config=my_file.config input.evio

* J2: hd_root --loadconfigs my_file.config input.evio

In addition, a few common parameters had to be changed:

* J1: EVENTS_TO_KEEP, JANA_CALIB_CONTEXT

* J2: jana:nevents, jana:calib_context


If you are using any plugins or programs which are not in the git 
repository, this page will help you to adapt your code to the new 
dependency:

https://jeffersonlab.github.io/JANA2/#/jana1to2/jana1-to-jana2


This wiki page was used to track the entire transition process:

https://halldweb.jlab.org/wiki/index.php/Transition_to_JANA2


-- 
Alexander Austregesilo

Staff Scientist - Experimental Nuclear Physics
Thomas Jefferson National Accelerator Facility
Newport News, VA
aaustreg at jlab.org
(757) 269-6982