Intel Xeon-Phi Coprocessor

73 Pages·2013·3.04 MB·English

C-DAC Four Days Technology Workshop
ON
Hybrid Computing – Coprocessors/Accelerators
Power-Aware Computing – Performance of
Applications Kernels
hyPACK-2013
Mode 3 : Intel Xeon Phi Coprocessors
Lecture Topic :
Intel Xeon-Phi Coprocessor : Prog. Env
Venue : CMSD, UoHYD ; Date : October 15-18, 2013
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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An Overview of Prog. Env on Intel Xeon-Phi
Lecture Outline
Following topics will be discussed

 Understanding of Intel Xeon-Phi Coprocessor Architecture

 Programming on Intel Xeon-Phi Coprocessor

 Performance Issues on Intel Xeon-Phi Coprocessor
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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Intel Xeon Phi - Coprocessor :
Multi-to-May-Core Processors : Background
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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Programming paradigms-Challenges
Large scale data Computing – Current trends
Trends Computing - Observations
How to run Programs faster ?
Super Computer
You require
Era of Single - Multi-to-Many Core - Heterogeneous

Computing
How to run Programs faster ?
Sequential Computing
 Fast Access of data
 Fetch/Store
 Fast Processor
 Compute

 More Memory to Manage data
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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Dual Core Processor
Conceptual diagram of a
dual-core CPU, with
 CPU-local Level 1 caches,
and
 Shared, on-chip Level 2
caches
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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Relationship among Processors, Processes, &Threads
µP Processors
Processors
i
Processes
. . . Map to MMU
OP OP OP

1 2 n
Map to
. . . Processors
Threads T T T
1 2 m
µP : Processor OP : Process T : Thread MMU : Main Memory Unit
i 1 1
Source : Reference [4],[6], [7]
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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Multi-threaded Processing using Hyper-Threading Technology

 Time taken to process n threads on a single processor is significantly
.
more than a single processor system with HT technology enabled

Multithreading Hyper-threading Technology
App 0 App 1 App 2 App 0 App 1 App 2
T0 T1 T2 T3 T4 T5 T0 T1 T2 T3 T4 T5
Thread Pool Thread Pool
CPU CPU
CPU T0 T1 T2 T3 T4 T5 LP0
T0 T2 T4
LP1
Time T1 T3 T5
CPU
2 Threads per
Time
Processor
Source : http://www.intel.com ;
Reference : [6], [29], [31]
P/C : Microprocessor and cache;
SM : Shared memory
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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System View of Threads
Threads Above the Operating System

 Understand the problems - Face using the
threads – Runtime Environment

Defining and
Operating Executing
Preparing
Threads Threads
Threads
Performed by Performed by Performed by
Programming OS using Processors
Environment Processes
and Compiler Showing return trip to represent that after
execution operations get pass to user space
Flow of Threads in an Execution Environment
Source : Reference [4],[6], [7]
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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Architecture-Algorithm Co-Design
30
e
New instructions
d
o Cache improvements
c 25

HW thread scheduling
l
a
i
Baseline
r
20
e
s

t
s 15
e
B

.
10
s
v

p
u 5

d
e
e
0
p 
S 1 2 4 8 16 32 64
      
Number of cores

Source : http://www.intel.com
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GPU Computing : Think in Parallel
Performance = parallel hardware

+
scalable parallel program
GPU Computing drives new applications
 Reducing “Time to Discovery” Application
 100 x Speedup changes science & research
methods
CPU GPU
New applications drive the future of GPUs
 Drives new GPU capabilities
 Drives hunger for more performance
Source : NVIDIA, AMD,References
C-DAC hyPACK-2013 An Overview of Xeon Phi Coprocessor Prog. Env
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