Transcript information - Indico

Monte-Carlo Event Database:
current status
Sergey Belov, JINR, Dubna
Outline
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Introduction
CMS MCDB – pros and cons
Main features of LCG MCDB
Main interfaces
Technical implementation
Current project status
Future plans
Introduction
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Correct Monte Carlo simulation of complicated
processes requires rather sophisticated expertise
Different physics groups often are in need of the
same MC samples
Public availability of the event files speeds up
their validation
Central and public location where welldocumented event files can be found would be
very useful
CMS MCDB
Problems
Advantages
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Based on web
technologies
Stores detailed
documentation for each
set of event samples
Storing data on AFS let
make its easy of access
Provide rapid
communication between
users and experts
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Stores parton level events
only
The expected number of
physics processes in the
database is several hundred
(data are stored on AFS so
there is a space limitation)
Cannot serve sophisticated
queries owing to it isn’t SQL
based
Main features of LCG MCDB
The most important reason to develop LCG MCDB
is to expel the restrictions of CMS MCDB
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An SQL-based database
Wide search abilities
Possibility to keep the events at particle level as well as
at partonic level
Direct programming interface from LCG collaboration
software
Inheritance of all the advantages of the predecessor CMS MCDB
General conceptions and terms
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Event file (sample) – the file containing particle or
partonic events
Article – a document describing the set of samples
Event data – the events themselves, all the data are
stored into event files
Event metadata – information which describes all
events in a sample in general (beam description, physics
parameters, applied cuts, etc.)
MCDB interfaces
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Search form
Article management (creating, changing, removing)
Downloading sample files
User management (registration, editing profiles,
removing)
Editing metadata on physical models and parameters
Moderating articles and user comments on them
Application programming interface to allow programbased article creation
Comment the articles
Access ways to LCG MCDB
End-User
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Read articles, comments, news
Download event files
Author
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Post articles and upload event files
Post news and answer the comments
Moderator
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Manage users profiles
Moderate articles and comments
Administrator
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Control the system
Technical database management
Application software
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Automatic articles posting and samples upload
The most common operations with
MCDB
Users in general
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Browses articles via the tree view of physics categories
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Searches by author, title, keywords, physical processes,
parameters values, etc.
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Downloads desired sample after agreement on MCDB
License
Articles’ authors
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Uploading event files
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Completing article with the information that wasn’t not
included in the description of an event file
Software selection
MySQL
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(DB management system)
Supported as a standard software in CERN LCG collaboration
Free and open source software
Very fast database operations
Reliable and stable
Doesn’t have good developed DB consistency support
Perl
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(programming language)
Stable, cross platform programming language
Powerful and easy-to-develop
Open source software
Has wide choice of free modules for many purposes
Apache
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(web server)
Powerful and flexible HTTP server
Highly configurable and extensible with third-part modules
SQL tables in MCDB
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Authors
Articles
Categories
Generators and their parameters
Models and parameters names
Model parameters’ values
Processes, initial and final states
Applied cuts
Event files, graph files
and a few other tables
SQL tables structure
Current status of LCG MCDB
By now was developed as a preliminary:
1) Design of MCDB web site
(available at http://top.sinp.msu.ru/lcg)
1) SQL tables structure
2) Articles and authors management system
3) Users privileges schema
Main Perl modules to create/modify
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Raw DB access (connection, queries)
Operating with tables (managing users,
articles, models, etc.)
Article authors helper
Security check for man-written texts
(articles body, user comments, news)
Logging module
Further plans for next two months
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Create or amend all base Perl modules
described above
Make the following interfaces: article
posting, articles management and users
management
Write detailed documentation and
database consistency rules for develores
Develop the site mailing system