The UKQCD collaboration workshop “HackLatt 2006” was held at the national eScience Centre (NeSC) in Edinburgh from 28 until 30 of March. The workshop was organised by the UKQCD collaboration and EPCC as part of the QCDsupport efforts for the members of UKQCD.
This report gives a summary of the contents, the organisation and output of the workshop. Section 2 describes the motivation of the workshop and section 3 describes its structure and contents. Section 4 gives a summary of the feedback received from the participants. The final section 5 contains the conclusions, an outlook and the acknowledgements.
The UKQCD collaboration has been running codes in production on the QCDOC
Super Computer at the ACF for a year, building up several Tbytes of data. There is an extensive hardware and software infrastructure available to collaboration members to access and postprocess the existing data, as well as producing further data. The key aim of this workshop was to enable the members of UKQCD to use this state-of-the-art infrastructure to produce cutting edge scientific results.
The workshop lasted for three full days. The program consisted of lectures, demonstrations and practicals. Table 1 gives the actual program of the workshop.
The workshop started with an overview of the hardware, software and data infrastructure available to UKQCD. It then went on to discuss the individual
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Table 1: Program of the workshop
Tuesday 28 March
9:00 Registration
9:30 Welcome
9:45 Computations Infrastructure
10:15 Physics: 1 year of QCDOC
11:00 Coffee
11:30 QCDgrid (lecture and demonstration)
13:00 Lunch
14:00 Algorithm I
15:00 Using QCDOC
16:00 Coffee
16:30 Using QCDOC (practical)
Thursday 30 March
9:00 OO and Templates
10:00 CVS
11:00 Coffee
11:30 CVS (cont.)
12:45 Lunch
13:45 The UK Hadron code
14:15 The UK Hadron code (practical)
14:45 HHHH++ (lecture & practical)
15:15 Coffee
15:45 Finishing session (finalising practicals)
C. Maynard
C. Maynard
R. Tweedie
D. Byrne
A. Borici
P. Boyle
P. Boyle
Wednesday 29 March
9:00 The Columbia Physics System (CPS)
10:00 CPS (practical)
11:00 Coffee
11:30 Algorithm II
M. Clark
M. Clark
A. Borici
12:30 Lunch
13:30 QDP++/Chroma
14:30 QDP++/Chroma (practical)
15:15 Coffee
B. Joo
B. Joo
15:45 finishing practicals (QDP++, Chroma, CPS, QCDOC) all tutors
19:30 Dinner
C. McNeile
J. Hein
J. Hein
R. Tweedie all tutors
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Overview on the UKQCD infrastructure components of the infrastructure in more detail. This was aimed at collaboration members who had limited or no experience on how to use them. To further aid with familiarisation, the individual lectures were supported by a practical session or a demonstration of the discussed infrastructure component. This included both hardware and software with detailed lectures on the main application codes and the UKQCD datagrid.
Intense work
In addition to these very closely very focussed agenda items, there were a couple of items aimed to explain the context of the infrastructure. These included an overview on the physics output from the first year running of QCDOC and a series of lectures and an exercise explaining the underlying Algorithms used for modern lattice QCD simulations. For collaboration members wishing to modify the codes, an introduction into object oriented code design, the use of templates and an introduction to the revision control software CVS was included in the program.
The session and teaching materials were prepared either by UKQCD members,
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with experience on the relevant component, invited external experts or by EPCC staff. The slides of the event are available on the internet. Interested collaboration members should visit: http://ukqcd.epcc.ed.ac.uk/training/2006/presentations.html
.
A total of 26 people, including speakers participated in the workshop. This number meets our expectation of 25 to 30 participants, prior to the workshop.
The home institutions include the UKQCD sites Edinburgh, Liverpool, Southampton and Swansea as well as Graz/Austria. The invited speakers are based in
Boston/UK, Jefferson Lab/US and Tirana/Albania.
Working in groups
To evaluate the workshop, we issued feed-back forms to the participants. The form asked ten questions, which had to be evaluated on a scale from 1 (very bad, inappropriate, . . . ) to 5 (very good, appropriate, . . . ). Thirteen forms have been returned. Table 2 lists the question and the average score received.
The workshop HackLatt 2006 offered detailed training on the hardware, software and data infrastructure available to UKQCD. The workshop was well attended and as the overall positive feedback shows, well received by the participants.
A follow on workshop in 2007 is anticipated. As some components of the
ILDG will become live during 2006, a greater focus on specific aspects of the data infrastructure of the UKQCD collaboration is expected.
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Table 2: Evaluation of the feed-back form
Question
Will the workshop training be of direct benefit to you in your work?
Was the style of the workshop (more or less participative, informal/formal etc) appropriate for you?
How would you access the general approach of the speakers/trainers to working with the group
Was the style of the discussion and instruction (more or less participative, informal/formal etc) appropriate for you?
How effective were the speakers/trainers in dealing with questions/queries?
How much has your understanding of this area been extended over the period of the workshop?
How effective were the workshop co-ordinators in dealing with questions/queries?
Did the group engage in debate and discussion?
score
3.9
4.0
4.4
4.3
4.7
3.5
4.6
4.0
Did the speakers/trainers facilitate discussion and questions
How useful will slides and printed materials from the workshop be to you?
4.1
4.4
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We would like to acknowledge the support from the National eScience Centre
(NeSC). NeSC offered administrational support, provided the venue and refreshments during the event. The Dinner was funded from the PPARC UKQCD collaboration travel grant (grant number PPA/G/S/2002/00467).
NeSC sponsored the travel of Dr B. Joo from Jefferson Lab in the US. The theoretical particle physics group at the University of Edinburgh sponsored the travel of Dr M. Clark from Boston, also in the US. The visit of Dr A. Borici from
Tirana in Albania was enabled by funds from the PPARC UKQCD collaboration travel grant. The program was organised and some of the materials have been developed and delivered by EPCC staff with financial support by PPARC (grant number PP/C504386/1).
We would like to thank all the speakers of the program for their excellent contributions.
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