DAQ Meeting/20180803

From PREX Wiki
Revision as of 19:37, 13 August 2018 by Cameronc (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Back to Main Page >> DAQ Documentation Portal >> DAQ Meetings

previous meeting << >> following meeting

Logistic information

BlueJeans calling instructions:
Toll-Free Number (U.S.& Canada): 888-240-2560
International toll number:     408-740-7256
Bluejeans CODE:         475 839 391
Bluejeans link: https://bluejeans.com/475839391


  • Bob : Editing Prex_ts_banks.crl to work and compile
  • Ciprian : revive panguin and other online analysis features
  • Brad Sawatzky : Github ideas and CODA Networking
  • Simona Malace : Understand and test the moller polarimeter DAQ


Bank Structures

  • In the .crl files, the "dirty trick" and the goto to "cont1:" are old and can be removed
  • Cameron should restore the comments in a safe, C friendly way (don't use # signs in comments)
  • Wait until injector studies are complete and done before modifying bank structures and testing the data map using xfcedump

Thinking about Online Analysis

  • Ciprian's last known working Panguin and Pan
    • Live in apar@adaq3~/PREX/pan/ and pan/panguin/
    • online.c and online.h is the online monitor
    • int main is the main program which creates a root TApp and creates pages based on a config file given as a command line argument
    • config file example: prex.cfg
  • Functioning Japan lives in ~apar/ciprian/japan/ and in ~a-onl/pking/japan
    • ~/ciprian/japan/Parity/prminput/prexin.conf is the functioning configuration for the injector that is being used right now
      • Looks at a .map file to map out the detectors in the .crl similar to old PAN control.db
      • There are multiple files now that contain different segments, for modularity
      • Label names in the .map file come out as the branch names in the JAPAN output
    • Then you get a MPS_tree (MPS = one pulse per event, see Meeting notes
      • A lot of the variables currently placed into the JAPAN output files are not necessary for online analysis purposes
    • PANGUIN functionality is to put the root file directly into RAM memory
      • So we should use a truncated output root file to speed up online data lookup - trimmed down analysis outputs exist
    • Startrun script ~/scripts/startAnalyzer_prex is required to run the online analysis (paired down version of regular analysis - runs fast and gives lots of updates)
      • ~/PREX/feedback/panFFB is the fast feedback code - this script reads last N events from the ET directly (rather than the memory resident root file), so it is susceptible to hanging - this feeds data into PANGUIN for online plotting - fast event rates will be a problem and needs to be updated (wont work for MOLLER unless paralleled to death with GPUs etc.)
        • These fast feedback executables will sometimes choose to block the ET whenever sequential events are unable to be read
        • This is so that you can make accurate helicity correlated beam corrections, etc. and not get back results due to pileup
        • We absolutely need to turn it off during production online analysis
        • There is a control.db for fast feedback that you can set to change beam, etc. parameters so that you can study beam quality, etc. in your raw data output
      • Prompt analysis is another analysis which is done automatically at the end of a run and reads the data written to disk (adaqfs)
      • WAC analysis is a third type of analysis is some sort of corrective post-analysis done by hand by Weekly Analysis Coordinators (WAC)
    • There are also some scripts that manage the Green Monster and EPICs to produce non-clean data runs that will be used as automated scans of parameters for beam tests, etc.
  • Memory resident root files are not currently functioning as intended
    • We need to write a script that puts files into memory and see if we can then use ROOT to access them
    • online.C inside ../pan/panguin serves as an example
      • GetDrawCommand() function parses a config file
    • How does a root file get stored in RAM memory, and how does root know where is lives in order to access it?
      • fConfig->GetRootFile() finds the root file
      • fConfig is defined in the initialization where it reads the config file

Networking Ideas

  • Brad Sawatsky says that Bob or I can make a new github repository in the JeffersonLab organization
  • There is nothing to prohibit github use, even by a shared account, except that ssh github usage is blocked by the hall gateway - just use the https:// technique instead
  • Iptables shouldn't be an issue for CODA running on new computers inside the hall
    • Bob should assign static IPs inside the Hall A subnet for new ROCs and computers that need to be inside the hall gateway
    • Then let the computer helpdesk know about them so they can get DNS name lookup turned on
    • Opening wifi should be ok, since it would be on a network separate from CODA (hardwired) - email Brad for more details

Moller Polarimetry

  • Cameron and Simona traced the wires of the Moller Polarimeter DAQ inside Hall A
    • We found that everything is basically as indicated in Roman's logic map, but some things are named weirdly
    • Simona will turn on the HV and look at noise and cosmics to ensure that the polarimeter and DAQ still work as they should
    • Simona will acquire some new modules so we have backups
    • Simona will fully trace all wires and the logic to make sure it is really working as it should
    • Cameron will document on the hallaweb wiki all of the notes that Simona makes while working


Today's testing