ATLAS Software Workshop Minutes

CERN, September 01 - 05, 1997

These minutes are still under construction; the finals are bound to be different.

Day	Time
Mon	09:00	Topic	Jürgen Knobloch: Introduction, Agenda
		References	N/A
		Summary	Workshops in the afternoon: Monday DIG 40-R-C10 14:00 ASP experiences 40-R-C10 16:00 Tuesday Database 40-S-D01 14:00 Wednesday Graphics 40-R-C01 14:00 ASP (testing) 40-4-C01 16:15 Thursday Atlas/CMS 40-5-A01
		Decisions	N/A
		Actions	N/A
	09:20	Topic	Sverre Jarp: RD47 (PCSF a.k.a HEPPC)
		References	Transparencies: Web
		Summary	One can LSF jobs from Unix to PCSF soon. This would be a workaround for the impossibility to submit jobs to this farm from outside CERN. ZEUS failed because realy only 1 person worked on it and there was too much time pressure.
		Decisions	N/A
		Actions	N/A
	09:50	Topic	Jürgen Knobloch: ACOS report
		References	Transparencies: Web
		Summary	New members: Helge Meinhard (domain manager), Ruediger Voss (muons), Maya (new librarian). Shows the agenda of the latest ACOS meeting.
		Decisions	N/A
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	10:05	Topic	Jürgen Knobloch: FOCUS report
		References	Transparencies: Web FOCUS minutes: Web
		Summary	Discusses what was discussed in the latest meeting
		Decisions	N/A
		Actions	N/A
	10:20	Topic	Laura Perini: LCB report
		Background	LCB Web pages
		References	LCB minutes: Text
		Summary	Overview of the LCB. Concluded : RD24,31,41. Ongoing: RD45, LHC++, 44, 47, Videoconferencing, Collaborative tools. Possible new projects: slow control, ROOT, SDE. Not only for projects. Composition: 3 Atlas, 3 CMS, 2 LHC-B, 2, Alice, and some other people. Frequency : every 2 months. Mandate shown. What to do to initiate a project : PAP, PEP, takes 4 months at least to get started. RD45 (referee Bob Jones). Are asked to provide a PEP in July. What about connecting a mass storage system? What about an alternative company? ROOT Only one of the experiments seems to be interested, so it is not becoming a common project for the LHC-B. LHC++ Use case for the licenses for LHC++. One of the priorities is the histogramming. GEANT4 Alpha version is coming out. Next plan should address the maintenance phase for after 1998. Videoconferencing It will be discussed later during this week. Members of the LCB from ATLAS are no longer ad personam but represent the experiment. They are supposed to present and discuss agenda items for the LCB in the appropriate ATLAS meetings beforehand.
		Decisions	N/A
		Actions	N/A
	10:50	Topic	Chris Onions: Software Release Tools
		Background	See CVS working group page
		Decisions to be made	What is the deadline for having all existing packages integrated into the CVS repository?
		References	N/A (ask slides)
		Summary	/afs/cern.ch/atlas/software Currently ARVE and Graphics are converted ATLAS Software 97_6 release was decided to be converted. Use car2cvs to do this. Main problem: duplication of COMMON blocks (137 found) Rules for age have to be added to SRT. Packages to be converted : package responsibles, Steve O'Neale, Antonio Amorim, Gilbert Poulard, Traudl Hansl, Andrea dell'Acqua have been contacted. New software librarian will be involved strongly in maintaining all this. Compared to BaBar, all symbolic links have been removed, basically to be able to use it with NT. Rosemary asks for a clearer description of responsibilities. Who may check in new things? Domain responsibles. BaBar has some 160 "packages", we'll have something similar. Daq people are also using it and wrote an introductory user guide. A full manual is in the make by Lassi.
		Decisions	N/A
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	??:??	Topic	Helge Meinhard: GNATS
		References	Transparencies: Web
		Summary	GNU problem reporting system. Everybody can submit a problem, or query the database. Automatic notification of the package responsible. Can be used by email or the web. Already in use in IT. ATLAS wants to have a Gnats server on our workgroup servers or join in on the IT Gnats server. This is currently discussed in IT, Decision taken probably this week. Start thinking now about which categories we have and who are responsible?
		Decisions	N/A
		Actions	Start thinking now about which categories we have and who are responsible.
	??:??	Topic	Helge Meinhard: DIG report
		Background	See the minutes of the meeting on 03/07/1997, and the agenda of the meeting on 28/08/1998.
		References	Transparencies: Web
		Summary	DIG=Domain Interface Group. Related to OO software. Other relevant group is the support team. Domain Decomposition: some new domains, define better the decomposition. Organisation of reviews and ramp-ups. Naming convention group yet to get started. Discussed in somewhat more detail Event domain (presentation by RD) A document is needed describing the reasoning of our domain decomposition. Juergen's CHEP paper will be put up as Introduction to ATLAS software. Histogramming in C++: discussed later this week after Jamie’s presentation. Need to come up with recommendation before the next workshop in November. DIG meeting always on monday afternoon of the software week and one meeting in between the workshops. Domains have been defined and have started design, but this first decomposition will almost certainly change. Domain teams nominate their representative in the DIG together with the other responsibilities.
		Decisions	N/A
		Actions	N/A
	14:00	Topic	Extra DIG Meeting
		Present	Helge, Patrick, KB, Maya, Steve, Jim, Dave Mellon, Christov, RD, Julius, Roger, Toby
		Summary	Magnetic Field Kors Bos promised to contact Felix Bergsma about Magnetic Field calculations. Helge Meinhard will talk to Vital about Dubna. Katsuya Amago promised to provide the Geant4 class for fields. What domain? Flat domain space, so B is a domain. It extends Geometry. Have to find someone this week to take on the responsibilities for this domain. Steve suggests to send a mail around to find someone: Helge Meinhard will do this. Kors Bos and Helge Meinhard will sit together and re-collect what has been done so far. Domain Decomposition Steve will collect what is in StP with the Requirements. The domains are supposed to update or extend this. Steve will do it this evening. Possibly Roger Clifft+ Steve Fisher+ Kors Bos will re-consider this text this week. Integration of Graphics into ARVE In ARVE, almost everything from Julius Hrivnac's Graphics design is already implemented by Toby Burnett. Julius would like, to but doesn't want to make these changes now because the design is up very soon for review. The checked-in version (in the repository) of ARVE will contain this latest implementation. Utilities domain We agree we need a domain for some implementations which can be used in any other domain. Parsers and Proxies are the first candidates for this domain. We then also need someone to take care of it. Another function for that domain would be the liaison with LHC. Proxies are a pattern and we discussed how to treat them in Edinburgh. The Lightweight pattern from Lassi's work is also in that category. They would still logically be part of the Utilities domain. Redefine MuonSystem Propose to have a meeting on Wednesday 17:00 to discuss the MuonSystem review. Reconstruction Discussion on new OIG's with Patrick Hendriks, Roger Clifft, Kors Bos and anybody else from the Reconstruction domain on Tuesday 17:00 hrs. Control The Edinburgh plan was to take whatever there was from ARVE into Control but it turned out to be very little (only some 6 classes). Steve will reverse engineer still this week what's in there and make a design document. It will also contain Parameters. Can it also contain exception handling? The book "More Effective C++" contains a discussion on Exceptions which is worth studying. Steve Fisher will talk to Lassi Tuura this week. Parameters have been reverse engineered already through Patrick Hendrik's work. InnerDetectorSystem A meeting will be organized by Roger with Pop tomorrow to see where we are and see how we can make progress and to try to coordinate the work going on by various people like Peter Luthaus, Jim Loken, Armin Reichold, Alan Poppleton. Java Discussed shortly how we could incorporate Java code into our software. Toby Burnett expresses concerns about the Vitual Machine for Java every time there is a cal to Java. The Java virtual machine gets started only once and takes over Control and only gives control back after the run has finised when it dies. So effectively the Control via the GUI is all done in Java. It is not clear with the information we have if this can be done but Onne Peters is encouraged to carry on with the implementation of the ARVE window in Java. Steve will see what has to be adapted in the ASP to be able to work with Java design's and code. SLUG Class This is an class to integrate the main program of SLUG/DICE/GEANT into the ARVE world. Pop is very interested but doesn't have time. Steve O'Neale is interested but doesn't have enough C++ experience. Someone has to take it up and push it forward. Should be discussed with also Andrea dell'Acqua. Maya will organise a meeting this evening with the appropriate people. Note added later: this meeting took place and Andrea dell'Acqua agreed to implement this class.
		Decisions	N/A
		Actions	A document is needed describing the reasoning of our domain decomposition. Naming convention group yet to get started. Kors Bos promised to contact Felix Bergsma about Magnetic Field calculations. Helge Meinhard will talk to Vital about Dubna. Katsuya Amago promised to provide the Geant4 class for fields. Steve suggests sending a mail around to find someone for B domain: Helge Meinhard will do this. Kors Bos and Helge Meinhard will sit together and re-collect what has been done for Magnetic Fields. Steve will collect this what is in StP on domain specifications with the Requirements. Roger Clifft+ Steve Fisher+ Kors Bos will provide some extra text this week on Domain Decomposition. We then also need someone to take care of the Utilities domain. Have a meeting on Wednesday 17:00 to discuss the MuonSystem review. OIG's discussion with Patrick Hendriks, Roger Clifft, Kors Bos on Tuesday 17:00 hrs. Steve will reverse engineer the ARVE Control classes this week and produce a design document. Steve Fisher will talk to Lassi Tuura about exception handling this week. A meeting will be organized by Roger with Pop tomorrow on the InnerTrackerSystem. Steve will see what has to be adapted in the ASP to be able to work with Java design's and code.
	16:00	Topic	ASP meeting
		References
		Summary	What happens after a design review? How does the communication work within the group? Should the reporting back not be in the asp? Need more presentations about what people have done. Complaints from USA collegues that it's not easy to understand how ATLAS software works. We're planning to improve by having Monday morning for introduction to the ATLAS software. Should produce informal documents before any review describing the ideas behind the system which has been built. Testing needs to be taken up by interested person(s): Kors Bos will try to organize a meeting. Relation between SRT and the ASP have to be defined in detail: who is responsible for packages? who repairs bugs? who makes an official release? We would like to convert in using newsgroups At this moment we have mailing lists. EMails and NewsGroups could be used together. Gilbert, Helge Meinhard, Juergen Knobloch, Christov Sliva will discuss newsgroups later this week and propose something. Testing has an asp component. But there is also the concept of self testing classes and frameworks. KB promises to find a slot to have a one hour meeting on this subject with some people.
		Decisions	N/A
		Actions	Need more presentations about what people have done. Kors Bos will try to organize a meeting on testing this week. Relation between SRT and the ASP will have to be defined in detail Gilbert Poulard, Helge Meinhard, Juergen Knobloch, Christov Sliva will discuss newsgroups and propose something.
Tue	09:00	Topic	Steve O'Neale: SLUG/DICE/ATLSIM consolidation
		Background	Steve O'Neale's consolidation page.
		References	Transparencies: Web Consolidation Web pages, ATGEANT3216
		Summary	The objective of the consolidation effort is to produce a single package incorporating the batch and interactive features of SLUG, DICE, ATLSIM, together with GEANT(Atlas), GENZ, GENSLUG, GGENZ, ATRECON, ATRIG and the CERNLib libraries and code of 97a plus corrections... The adoption of tools such as SRT, CVS, cpp etc especially since CMZ is no longer supported is essential in order to facilitate the work of the programmers and the users. The resulting package, with a new name and structure to be decided upon, will be in the SLUG framework. ATGEANT3216 has been built based on the latest GEANT3 release (version 8) and includes several ATLAS changes (see ATGEANT3216 ). Experience with cpp in compilation and library installation has been discussed with the SRT/CVS working group. The consolidation of the ATLSIM package involves as a first step translation into FORTRAN and cleanup of duplicated code (see also ADA's transparencies). The treatment of pileup where ATLSIM is faster and of random number seeds and initialisation where general improvement is needed were presented. Extensive testing by the user community is required. An overall revamping of the documentation and subsequent documentation support are urgently needed.
		Discussion	A. Amorim said that a `datacard database' scheme (probably initially on WWW) is important for testing. Such a scheme exists for ATGEN datacards but further user seems to be hampered by the user `psychology'... An automated book-keeping system for all user jobs was also advocated. J. Knobloch emphasised that an update of the list of supported platforms in necessary. CERN-based repositories for non-supported platforms may still be available.
		Decisions
		Actions	CONSOLIDATE ; Identify names for the consolidated product inspired by domain decomposition in OO software; Remove all RNDM dependencies from ATLAS GEANT; Study direct access I/O in pileup; Review use of random number routines, particularly in digitisation; Establish testing groups for each distinct style of use of the consolidated product; Establish test samples in connection with physics groups; ATLAS management to review documentation tools and assign topics to people asking for work projects.
	09:00	Topic	Andrea dell'Acqua: SLUG/DICE/ATLSIM consolidation
		References	Transparencies: Web
		Summary	The aim of the consolidation project is to bring the current software into a coherent and maintainable state so as to allow the completion of the physics TDR and ensure a smooth transition to the OO software. One of the main issues is the merging of the mainly interactive ATLSIM program with the SLUG/DICE batch framework. A beta version of the resulting interactive/batch executable could be envisaged for end of September.
		Discussion	The definition and purpose of the consolidation were briefly discussed following a question raised by K. Sliwa. A. Amorim proposed the creation of a user `job database' for mapping the various uses of the software. The purpose and feasibility of this were debated. It was noted that an effort to collect the user requirements/expectations has already been carried out by J. Pater et al in the Inner Detector community. This has served as input to the consolidation effort. The dependence of the quality of the physics results on the software quality was emphasised. A measure suggested was to require the submission of the software used to obtain physics results together with the note in which these are published. At this point, it was noted that the compatibility of the two current software frameworks in terms of physics has so far largely been maintained.
		Decisions
		Actions	CONSOLIDATE ; Identify names for the consolidated product inspired by domain decomposition in OO software; Remove all RNDM dependencies from ATLAS GEANT; Study direct access I/O in pileup; Review use of random number routines, particularly in digitisation; Establish testing groups for each distinct style of use of the consolidated product; Establish test samples in connection with physics groups; ATLAS management to review documentation tools and assign topics to people asking for work projects.
	09:45	Topic	Gilbert Poulard: Status of 97_6 release
		References	Transparencies: PostScript
		Summary	The 97_6 version of the ATLAS software is the last CMZ release before the migration to CVS. It is essentially complete in terms of geometry (the muon code has been added) and reconstruction for the calorimeters and the Inner Detector. The trigger code (ATRIG) and the muon recontruction code remain to be added. An ATRIG/ATRECON executable has been requested by the physics community.
		Discussion	A. Amorim suggested an update to the latest version of PYTHIA. C. Onions pointed out that the inclusion of new code should be in the CVS rather than in the CMZ framework to avoid delays. G. Poulard argued that a CMZ version should not be too difficult provided it does not delay the migration.
		Decisions	N/A
		Actions	N/A
	10:30	Topic	David Candlin: Arve ramp-up evaluation results
		References	Transparencies with comments: PostScript, DVI, TeX
		Summary
		Decisions	N/A
		Actions	N/A
	10:50	Topic	Toby Burnett: Arve ramp-up status
		Background	See Toby Burnett's status page. The ramp-up is based on the results of the evaluation (see reports by Lassi Tuura and David J. Candlin) and the discussion in the Domain Interface Group (see minutes of meeting on 03 July 1997).
		References	Transparencies: Web
		Summary
		Decisions	N/A
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	11:30	Topic	Lassi A. Tuura: Arve ramp-up timescale
		References	Transparencies: Image
		Summary
		Decisions	N/A
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	13:30	Topic	A short meeting to identify improvements in ATLAS computing welcome and documentation, for newcomers.
		References	N/A (ask slides)
		Summary	A page of welcome (``page 0'') for newcomers, linked from the main computing page, with a brief description of ``everything'' in ATLAS computing, extended by links to other new pages of the same flavour, and links to regular computing pages. The style should be welcoming, with hints how to get involved. Improvements to the existing hyperlinks; the name-tags are sometimes misleading. (To old hands, the recent improvements have been good, but it seems more is required). Some of the references to ``ATLAS software'' in fact refer only to the FORTRAN. Some material (e.g. Arve) cannot be reached by clicking. Clean out obsolete pages. Sign and date all pages. More emphasis on what's active/current, to make it stand out. Joining in reviews: make it clear that you don't have to be an expert either on the deliverable or the ASP, but that it's a good way to get involved. What about promoting the use of newsgroups (discussed yesterday)? BaBar's hypernews was praised. What's happening about LIGHT?
		Decisions	N/A
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	14:00	Topic	Database meeting
		Background	The G3/Zebra to G4/Objy converter should be an issue.
		References	Agenda, Minutes
		Summary
		Decisions	N/A
		Actions	N/A
Wed	09:00	Topic	Jamie Shiers: LHC++
		Background	Jamie Shiers has been asked to report on the status, plans, and timescales for math libraries fitting programs histogramming STL (which version?) We'd also like him to discuss Licensing (Use cases: What do I need if I want to do ..., e.g. histogramming, interactive analysis; administration; installation of licenses (and software) Component interplay (Use cases again, see above; platform availability and compatibility) Support for LHC++ components
		References	Transparencies: Web
		Summary
		Decisions	N/A
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	11:00	Topic	Bob Jones: ATLAS DAQ Software Process
		Background	The main idea is to receive input for the Editorial Committee for the Atlas Software Process ASP.
		References	Transparencies: PostScript
		Summary
		Decisions	N/A
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	11:30	Topic	Katsya Amako: GEANT4 Software Process
		Background	The main idea is to receive input for the Editorial Committee for the Atlas Software Process ASP.
		References	Transparencies: Web
		Summary
		Decisions	N/A
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	14:00	Topic	Graphics meeting
		References	Agenda, Minutes
		Summary
		Decisions	N/A
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Thu	09:00	Topic	Hans-Peter Wellisch: GEANT4 Framework
		References	Transparencies: PostScript
		Summary
		Decisions	N/A
		Actions	N/A
	09:30	Topic	Andrea dell'Acqua: GEANT4 ATLAS Implementation
		Background	A definition of hits and digis objects is required such that work on the G3/Zebra converter to G4/Objectivity can start. Pile-up to be covered.
		References	N/A (ask slides)
		Summary
		Decisions	N/A
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	10:30	Topic	Maya Stavrianakou: Productions and LSF
		References	Productions transparencies: Web LSF transparencies: Web
		Summary
		Decisions	N/A
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	11:30	Topic	Sverre Jarp: Cocotime Request
		References	Transparencies: Web
		Summary
		Decisions	N/A
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	11:45	Topic	Steve Fisher: StP, CodeCheck
		References	N/A (ask slides)
		Summary	Steve told us about StP version 2.4 (beta release) which he has been testing on Windows NT. It has UML, but he has not yet tried it. He suggests that we should not change to UML too soon. The PC version of StP is very similar to the Unix version. You are provided with MKS (Unix style tools), a frame viewer, Sybase, an X server and FlexLm. It is designed to inter-work with Unix. For example Sybase could be on a Unix machine. A significant change to this version is that it no longer uses SNiFF+ as a parser for the class capture, but uses their own fuzzy parser. The comment capturing does not seem too good, so we make have to continue using the existing home made script for this. A few small changes have been made to the customisation of StP. A report generator to extract headers from requirements tables to generate a decomposition document has been written. It is now possible to exclude diagrams from a report and to control the displayed version number of a report. He then told us about CodeCheck, which is a parser for C++ which makes it very easy to write programs to check coding rules or to generate metrics. Many example programs are provided with the tool. It works in command line mode on Unix or PC, but can also be integrated with Visual C++ as a tool allowing one to jump quickly to code rule infringements. A program (of about 800 lines) allows 37 of the 79 Atlas Coding Rules to be checked. The others are either subjective or too hard to check with the current version of CodeCheck. A survey of recent work on OO metrics revealed that not many metrics had been validated, and that many validations had been carried out on student projects. Steve said that he was especially interested in metrics which can be extracted from the design and proposes to add these to StP design reports. He had looked at three metrics for implementation, Decisions per executable line, Operators per executable line and number of executable lines of code. He showed a distribution of executable lines of code for 147 functions, which indicated very small functions (about 4 lines). Design metrics considered were the depth of the class in the inheritance tree, the coupling between classes (number of distinct classes referenced) and the counts of public, protected and private methods. It was noted that the count of private methods could not be made at design time and the count of coupling between classes would depend upon whether the measurement was made at design time or from the code. Coupling for 31 classes he had looked at showed a peak at around 2. Finally he observed that there were still problems with the parser being unable to cope with some STL, but that the company fixed bugs very quickly and that he hoped to soon be able to recommend purchase of the product.
		Decisions	N/A
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	12:00	Topic	RD Schaffer: Database Working Group Report
		References	Transparencies: PostScript
		Summary
		Decisions	N/A
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	12:00	Topic	World Wide Computing meeting
		References	Agenda, Minutes
		Summary
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Fri	09:00	Topic	Krzysztof Sliwa: Word Wide Computing Workgroup Report
		References	Agenda, Minutes
		Summary
		Decisions	N/A
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	09:20	Topic	Julius Hrivnac: Graphics Workgroup Report
		References	N/A (ask slides)
		Summary
		Decisions	N/A
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	09:40	Topic	Kors Bos: Summary of Decisions
		References	N/A (ask slides)
		Summary
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	10:10	Topic	Jürgen Knobloch: Planning for Next Cycles
		References	N/A (ask slides)
		Summary
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	11:00	Topic	Helge Meinhard: Dates of 1998 Workshops
		Background	Must take into account Barcelona workshop on LHC computing (tentatively: ...) CHEP conference (September or October) Atlas weeks (tentatively: 02/03 to 06/03; 08/06 to 12/06; 14/09 to 18/09; 16/11 to 20/11) Atlas Physics workshop (Grenoble, 28/03 to 04/04) One workshop should be held outside CERN (US?)
		References	N/A
		Summary	Tentative 1998 calendar: 23/02 - 27/02 Software workshop, CERN 02/03 - 06/03 Atlas week, CERN 28/03 - 04/04 Physics workshop, Grenoble 04/05 - 08/05 Software workshop, CERN 08/06 - 12/06 Atlas week, CERN 24/08 - 28/08 Software workshop, US (alternatively: 07/09 - 11/09) 31/08 - 04/09 CHEP conference, Chicago 07/09 - 11/09 Software workshop, US (alternatively: 24/08 - 28/08) 14/09 - 18/09 Atlas week, CERN 16/11 - 20/11 Atlas week, CERN 07/12 - 11/12 Software workshop, CERN
		Decisions	N/A
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	??:??	Topic	Working Group Meeting on Testing
		References	Transparencies: PostScript
		Summary	The slides briefly list: The topics we wanted to look at: what testing should be done, who should do it and when. Rosemary's outline of a possible procedure - this was to provide a concrete basis for discussion and was not a firm proposal. Things we might do before the next meeting.
		Discussion	It was not possible to come up with definitive plans without further work, but there was a lot of usful input about things we might look at. These are some of the topics. Look at testing tools and see how much testing can be automated. Define different types of tests: for correctness, accuracy and performance. Look at comparative testing on different platforms. Do we really need a "Test Coodinator"? What's the relation of testing to maintenance and the role of the software librarian? How can we associate tests with classes and with "packages" performing particular computations? How can physicists in general contribute to testing? There was also some discussion of the extent to which we could follow industry practice and keep testing independent of implementing. It was felt that on the whole we had too few people to be able to do this, and from a practical point of view, most of the tests had to be devised by the same people as wrote the code. However, we may be able to persuade small groups of people to swop tests between themselves. There is also a role for independent testers (who may be volunteer users) to do spot checks or to test especially important parts of the code. There was little enthusiasm for the "bazaar" method of developing code (more or less what we had at the moment!) because physicists in general do not form a pool of enthusiastic code hackers and want their code to be of good quality as soon as it is released.
		Decisions	We will not decide on "what should be tested" until we have a better idea of what can be automated. We will look at a realistic computation, and see what tests would be desirable. We will try and construct some standard data sets and output that can be used for reference in testing current and future software.
		Actions	Steve Fisher will investigate tools- both those commercially available and those that are used in HEP. Julius and Roger will look at the testing requirements of IPATREC, taking it as an example of a realistically large computation. Rosemary will write something for the ASP document (to make a start on getting something about testing on the record). Maya and Steve O'Neale will construct some standard reference data sets.