Executive Committee Meeting - 21/6/2016 (Onera, Toulouse)

Minutes -

It was the first meeting of the Tango consortium after signing the collaboration contract between 8 partners


  • Jean-Michel Chaize: Coordinator
  • Andy Gotz: Chairman representing ESRF
  • Alain Buteau: representing SOLEIL
  • David Fernandez: representing ALBA
  • Claudio Scafuri: representing ELETTRA
  • Thorsten Kracht: representing DESY
  • Wojciech Kitka: representing SOLARIS
  • Lorenzo Pivetta: representing INAF on behalf of Cristina Knapic


  • Vincent Hardion. Therefore MAXIV had no representative


  • Lajos Schrettner representing ELI-ALPS

State of the collaboration contract:

  • Only INAF has not signed the contract yet. Latest news is that all the details have been agreed with the INAF administration. The main concern was about the VAT. The fee of 10000 Euros has been confirmed that it is VAT-free becaue it is a collaboration contract and not a purchasing of a product. For INAF, the contract is in the hands of the administration at the head quarters of Roma and should be signed in the weeks to come
    • Decision: ESRF will send out the bill to each partners even if INAF has not yet signed. Unanimous vote.
    • Info: ESRF lawyer says we cannot sent the bill out until everyone has signed. - we wait for INAF to sign hopefully by next week
  • Andy informed that several institutions requested to become members in the months to come. The institutes are SKA Office in UK, SKA South Africa, ELI-Beamlines and ELI-ALPS.  Concerning ELI, Lajos Schrettner informed the committee that the 3 ELI pillars will be regrouped in a single institution in 2018 and the contract may be signed by this institution named ELI-DC. No clear status can be given in this stage.
  • Alain raised the following question: Should we accept  subscriptions for different departments of the SKA project: Andy and Lorenzo answered that the different SKA are actually different entities located in different countries with independent financing. Therefore they should be considered as different institutions.
    • Decision: The committee accepts unanimously the subscription of the 2 new candidates (SKA office  and SKA South Africa) to take effect on the 1st of January 2017. Unanimous vote.
    • The case of the ELI pillars need to be clarified once the head quarters have given their answer to the ELI pillars representatives.
  • All the delegates agree to ask ESRF to not impose a new-signature of all institutions for each new comer. An individual signature between ESRF and the new comer is preferable and a simple information can be sent to the other representatives

Discussion about the budget:

  • ESRF asks if the delegates accept to be consulted via email for budgetary decisions
    • Decision: The committee accept that the decisions for the budget can be made via email
  • The budget was presented by ESRF, the following lines have been discussed and accepted.
    • Rewrite the documentation: OK for outsourcing to a company with technical writing skills
    • Prepare the V10: We should nominate a group of people to define the objectives and nominate a head of project. The working group will be composed during the Tango meeting and lead by Andy Gotz.OK for outsourcing in these conditions.
    • Prepare a device server catalog: OK for outsourcing to 3-controls with the presented specifications
    • Improve packaging (Debian and other platforms): OK
    • Maintenance and hosting of web site and mailing list: OK to outsource to Webu
    • Maintenance contract for OmniORB: OK to combine the maintenance contracts of ESRF and SOLEIL into one maintenance contract
    • Travel for kernel group: OK to finance the travel of kernel developers to ESRF
    • Remained to be discussed: buffer  for coordination, business development, and management.
    • Decision: The committee approved the presented budget. Unanimous vote

Move to Git

  • Decision: The committee approved the technical proposal to move to git but did not nominate who will do this. Unanimous vote
  • TODO: members to designate the list of people to be involved in the move to git (especially for the tango-cs projects).


  • Andy presented the database paper by Soleil and said that some of the issues, especially the performance, have been addressed but that other issues like cleaning up the tables after deleting a server were not yet addressed. It was agreed that this work is well identified and could be sub-contracted.

Discussion about documentation and packaging

  • We agree to say that we need to enhance the documentation for the new comers. i.e. Tango overview, Getting started, Installation guide, Architecture guide, Howto.... We have a good documentation targeted to programmers but we need more documentation for general architecture. The new documentation should preferably written by a user of Tango and not a kernel developer.
  • Another document recommending a good strategy for backuping a control system would be very useful: e.g. how to setup a database replication and backup the replica.
  • Decision: OK to proceed with an external technical writer. The documents should be tested by a new comer. Unanimous vote
  • Thorsten propose somebody (Eugen Wintersberger) to take care of the packaging.

​​Long term support (LTS)

  • Several members requested a Long Term Support of the previous versions of Tango. i.e. continuing to correct bugs or apply patches on the previous releases even if the next version is available.
  • Several member said that it was a big job to change the version of the system and check each device server with the new version.
  • Jean-Michel reminds that the modularity and the backward compatibility of TANGO allows easily to install the latest version of TANGO on a system without having to recompile all the device servers and applications.  ESRF uses this strategy on the accelerator. The latest library is installed immediately after the official release. Since the device servers are not recompiled, they continue to use the previous release until they are recompiled. The recompilation is then done step by step with very little risks. If a bug is detected on a server using Vn-1, this particular server is recompiled to take benefit of the last evolution of the library
  • Other institutes generally use a stricter strategy, imposing recompiling all the servers when a new release is installed. This strategy increases the risk of simultaneous deployment of the new version. Anyway, to take care of the long term support, we would need more resources, until now, nobody had the time to do this support and no budget is available for that. This point can be addressed if the community has more budget to dedicate somebody for that. 

Collaboration operation issues.

  • We observe that the answers to the forum is mainly done by ESRF and few others. All members were reminded that they should help in spreading and sharing the knowledge of Tango by designating at least one person in their team to answer questions on the forum.
  • Ticket followup: Alain asked for a better follow up of the tickets for assigning them and follow them up. The problem is mainly a man power issue. 
    • Each delegate is requested to collect and prioritize their tickets and send them to ESRF for a further discussion at least once a year before each Tango meeting. It should be done more often for urgent issues.
  • Alain requested a clarification about which projects are official for tango and which ones are not officially supported. He referred for instance to RestAPI which is available but not maintained by one of the collaboration member institutes on the long term. He took also the example of the archiving, where 2 different incompatible projects (HDB/TDB and HDB++) are available and it is not clear for newcomers, which one is the official one.
    • Andy answered that  large open source projects have often external contributors with no warranty of maintenance. The RestAPI is in very good hands (Igor form HZB). Anyone who is interested in using contributions should get more involved in order to help with the maintenance. This is standard practice in Open Source projects. For the HDB/TDB and HDB++ projects Andy proposes that the newer project (HDB++) becomes the official archiving solution in the near future because it has been developed more recently and implements a number of features which were missing in HDB e.g. multi-nethost, millisecond timing etc. The committee took note of the issue but no decision was made on this point.

Next Tango meeting​

  • INAF is proposed as the organiser of the next Tango meeting for the 1st half of June 2016 (To be confirmed).   If not confirmed DESY has offered to organize it.