Luke Kreczko of CERN, presented at Bristol ITMegaMeet 2013 CERN hosts many experiments and accelerators. One of them, the Large Hadron Collider (LHC), is the world's largest particle accelerator. Its experiments produce enormous amounts of data which is analysed using the LHC Grid. I will describe the Grid framework developed for the CMS experiment that produces around 20PB of data every year and processes it in regular intervals.

1. The
LHC
Grid
High Performance Computing in
High Energy Particle Physics
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
1

2. $
whoami
• Lukasz
Kreczko
–
ParGcle
Physicist
• Graduated
in
Physics
from
University
of
Hamburg
in
2009
• 2009
–
2013
PhD
in
ParGcle
Physics
at
the
University
of
Bristol
• Currently
CompuGng
Research
Assistant
at
the
University
of
Bristol
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
2

3. The
experiment:
a
big
digital
camera
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
3

4. The
experiment:
a
big
digital
camera
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
4
40
million
“pictures”
per
second
Each
“picture”
around
1
MB!

5. The
data:
a
structured
mess
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
5

6. The
data:
a
much
nicer
picture
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
6
Muon:
pT = 71.5 GeV/c
η = ‐0.82
Missing ET:
22.3 GeV
Jet:
pT = 89.0 GeV/c
η = 2.14
Jet:
pT = 85.3 GeV/c
η = 2.02
Jet:
pT = 90.5 GeV/c
η = ‐1.40
Run: 163583
Event: 26579562
Jet:
pT = 84.1 GeV/c
η = ‐2.24
m(F)=1.2 TeV/c2
_

7. The
goal:
extend
our
knowledge
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
7
Muon:
pT = 71.5 GeV/c
η = ‐0.82
Missing ET:
22.3 GeV
Jet:
pT = 89.0 GeV/c
η = 2.14
Jet:
pT = 85.3 GeV/c
η = 2.02
Jet:
pT = 90.5 GeV/c
η = ‐1.40
Run: 163583
Event: 26579562
Jet:
pT = 84.1 GeV/c
η = ‐2.24
m(F)=1.2 TeV/c2
_
Billions
of
+
simulaGon
(GeV)γγm
110 120 130 140 150
S/(S+B)WeightedEvents/1.5GeV
0
500
1000
1500
Data
S+B Fit
B Fit Component
σ1±
σ2±
-1
= 8 TeV, L = 5.3 fbs-1
= 7 TeV, L = 5.1 fbsCMS
(GeV)γγm
120 130
Events/1.5GeV
1000
1500
Unweighted

8. The
goal:
extend
our
knowledge
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
8
Muon:
pT = 71.5 GeV/c
η = ‐0.82
Missing ET:
22.3 GeV
Jet:
pT = 89.0 GeV/c
η = 2.14
Jet:
pT = 85.3 GeV/c
η = 2.02
Jet:
pT = 90.5 GeV/c
η = ‐1.40
Run: 163583
Event: 26579562
Jet:
pT = 84.1 GeV/c
η = ‐2.24
m(F)=1.2 TeV/c2
_
Billions
of
+
simulaGon
(GeV)γγm
110 120 130 140 150
S/(S+B)WeightedEvents/1.5GeV
0
500
1000
1500
Data
S+B Fit
B Fit Component
σ1±
σ2±
-1
= 8 TeV, L = 5.3 fbs-1
= 7 TeV, L = 5.1 fbsCMS
(GeV)γγm
120 130
Events/1.5GeV
1000
1500
Unweighted
That’s
the
famous
Higgs
boson

9. Analysing
all
data
• CMS
records
10
000
Terabytes
of
data
every
year
(around
70
years
of
full
HD
movies)
• +
same
amount
of
simulaGon
• To
analyse
this
on
a
single
computer
would
take
64,000
years!
9

10. Analysing
all
data
• CMS
records
10
000
Terabytes
of
data
every
year
(around
70
years
of
full
HD
movies)
• +
same
amount
of
simulaGon
• To
analyse
this
on
a
single
computer
would
take
64,000
years!
10

11. The
compuGng
model:
the
decision
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
11

12. The
compuGng
model
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
12

13. The
compuGng
model
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
13
Bristol
is
one
of
the
T2
centres

14. The
computer
centres

15. All
over
the
world

16. All
over
the
world
On
a
normal
day,
the
grid
provides
100,000
CPU
days
execuGng
1
million
jobs

17. PhEDEx:
A
Bristol
invenGon
• short
for
“Physics
Experiment
Data
Export”
• Sodware
for
data
placement
and
the
file
transfer
system
• Development
started
in
Bristol
• One
of
the
main
developers
(now
at
Cloudant)
is
giving
a
talk
later
today
“Your
Database
to
the
Cloud,
an
Intro
to
Cloudant
NoSQL”
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
17

18. PhEDEx:
The
components
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
18
Transfer
agent
Transfer
management
database
Management
agent
Tools
to
manage
transfers
Local
agents
Web
monitoring

19. PhEDEx:
data
monitoring
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
19
150
PB
70
PB
hjp://www.flickr.com/photos/paulrossman/6555010435/sizes/l/in/photostream/

20. Current
and
future
topics
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
20
Things
changed:
Network
is
genng
cheaper
as
well

21. Current
and
future
topics
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
21
Things
changed:
Network
is
genng
cheaper
as
well
We
are
moving
into
the
cloud

22. Current
and
future
topics
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
22
Things
changed:
Network
is
genng
cheaper
as
well
We
are
moving
into
the
cloud
Any
data
anywhere!

23. Other
current
and
future
topics
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
23
Protocol
buffers
CouchDB
Hadoop
Provisioning
of
compuGng

24. Summary
&
Outlook
• The
LHC
grid
is
a
world-­‐wide
distributed
compuGng
network
that
makes
discoveries
possible
• The
grid
is
changing
to
adopt
to
current
technologies
• In
two
years
Gme
the
LHC
will
increase
its
energy
to
14
TeV
–
more
data,
more
discoveries
to
come!
Saturday,
1
June
13
Lukasz
Kreczko
-­‐
Bristol
IT
MegaMeet
24