Linux Cluster System

1
Linux Cluster System

• Dept. Computer science and Engineering
• Moon Jun Hyun
• imp_at_bravo.kwangju.ac.kr

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Contents

• Linux Cluster Architecture
• Parallel Computer Architecture
• Cluster Architecture
• Linux Cluster Architecture
• Linux Cluster System Composition
• Hardware System Selection
• Node Network Configuration Composition
• Parallel Configuration Composition
• MPI Linux Cluster Programming
• Parallel Programming
• MPI Programming
• MPI Function

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Linux Cluster Architecture

• Parallel Computer Architecture
• Cluster Architecture
• Linux Cluster Architecture

4
Parallel Computer Architecture

• ?? ???? ??
• ??? 2? ??? CPU? ??
• ?? ?? CPU? ??? ?? ??? ????
• ?? ?? ? ???? ?? ??
• CPU?? ??? ??? ??? ???? Counter? ??
• Parallel processing computer
• Seraial processing computer
• ?? ???? ???? ??? ?? ?????? ?? ?
• ??? ??? ????? ???? ???? ??
• ?? ????? ???? ???? ????? Construct(array,
  Control structure, Procedure, Resursion)? ?? ??
  ?? ???? ???? ?? Programming

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Parallel Computer Architecture(cont.)

• ?? ???? ?? ??
• ??? ??? ?? ?? Coarse grained vs Fine grained
• Flynns ?? SISD, SIMD, MIMD, MISD
• ??? ??? ?? ?? Distributed memory, Shared
  memory, Distributed-share memory
• ??? ??? ?? ??? ?? ?? Switch, Hardware supported
  remote momory access by direct memory access,
  Router chip(or processor), etc
• ??? ??? ??? ?? ?? Hypercupe, 2-D mesh, 3-D
  torus, switch, etc
• Single system image vs Multiple system image

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Parallel Computer Architecture(cont.)

• ?? ????? ?
• ??
• Superscalar architecture? ?? ?? ???? ??
• ?????? X(i)? Y(i)? register? ?? ???.
• X(i)? Y(i)? ???.
• ?? ??? ?? register?? Z ??? ??? ??.
• ? ??? loop? ?? ?? ????.

do i 1, MAX Z(i) X(i) Y(i) enddo
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Parallel Computer Architecture(cont.)

• ?? ???? ??
• MAX ?? X(i)? Y(i)? N?? ???? ??? ??? (MAX/N) ????.
• MAX/N?? X(i)? Y(i)? ??? ???? ???? ??? N?? ????
  (MAX/N)? ????.
• ??? ??? Z(i)? ? ?? ???.

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Parallel Computer Architecture(cont.)

• Amdahls law ???? ?? ?? ?? ???
• ??? ??? ??? ?? ? ???? ??? ??? ????? ????? ??? ??
  Ip
• ??? ??? ??? ?? ? ???? ??? ??? ????? ????? ??? ??
  Is
• ?? ?
• ?? ?? Ip? 90, Is? 10? ?, ?? N? ????? ???? ??
  ??? ?? (0.90.1)/(0.9/N0.1)10?? ????.

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Parallel Computer Architecture(cont.)

• Prallel computer?? ???? ???? ??? ?? system
  overhead ???, ???? ?? ?? ??? Is ? 0? ???? ???
  ??? ?? ???? ??
• ??? ??? ???? ??? ??? ??? ??(surface)? ? ??? ????
  ??(volume)?? ???? ??? ????? ?? ???? ??? ??.
  (surface-to-volume retio)

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Cluster Architecture

• Prallel Computer Architecture
• MPP(Massively Parallel Processing) CRAY T3-E
• SMP(Symmetric Multi-Processing) Pentium II, III
  CPU
• Cluseter Architecture
• MPP architecture
• Loosely-coupled parallel architecture
• ??? ??? ??? ???? ???? ??? ? ?? ??? ?? ???? ?
• Distrubuted computer architecture
• Dynamic load balancing, high availability
• ???? ????(OS)? ??? ?? ?? ???? ?? ?? task? ?????
  ???? ???? ?

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Cluster Architecture(cont.)

• Parallel Computer vs Cluster Computer
• Prallel computer
• ??? ?? Latency, Bandwith
• Cluster computer
• Job scheduleing, Resource allocation
• Beowulf Cluster
• High performance computing platform
• ??? ??
• High performance computing
• High availiability system
• Data base server
• Web server

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Linux Cluster

• Cluster? ? ?? ????? Linux? ???? Cluster
• Open source? Linux ????? ???? off-the-shelf
  componets? ??? ?? ??? ?? Cluster? ?? ??
• ??? CPU? Hradware ??
• ???(generality) Linux ??? ?? ??? ????? Cluster?
  ?? ??
• ???(efficiency) ???? ??? ???? ??? Cluster ??
  ??
• ?? ???? PC? Network ??? ?? ??? ??

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Linux Cluster(cont.)

• Architecture potability
• ?????? ???? ??
• Upgrade? ???
• Software potability
• De facto standard?? message passing paradigm
  implementation? ?? ????? ??? ???
• Scalability
• ???? ?? Architecture
• Avalon? ?? 140?? Alpha PC Fast Ethernet ??
• ??? ???
• ????? Compiler ??, Network component ?? ?? ?? ???
  ???? ?? ???? ???? ??? ? ? ?

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Linux Cluster System Composition

• Hardware System Selection
• Node Network Configuration Composition
• Parallel Configuration Composition

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Hardware System Selection

• ??? ????
• ??? ???
• ??? ??? ?? ??? ?? ??
• ??? ??(??? ???? ?)
• ??? I/O(??? ?? ??? ??? I/O ??)
• ?? CPU
• Inter vs Alpha (or other)
• Single CPU vs SMP
• ?? ???? ???(Synchronization) ??? ?? ?? ?? ????
  ??? ?? ??? ????.

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Hardware System Selection(cont.)

• ??? ??? ??? ???? ??
• Fast Ethernet 100 Mbps Switch
• Myrinet NIC Myrinet Switch
• Gigabit Ethernet Gigabit Switch
• SCI SCI Switch
• ATM Card ATM Switch (?)
• PLIP (?)
• Hard disk system ??
• Big disk diskless
• Disk on every nodes
• Local disk and I/O disk

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Hardware System Selection(cont.)

• Serial console or not
• ????? ?
• ??? ??? ??? ??? ??? ??
• Switch ??? ?? ??? ?? ??? ??? ????.
• Multi-level switch, Channel bonding
• Multiple networks
• Hard disk system? ??? ??
• Share noting(Distributed file system)
• Share something(Local partition NFS partition)
• Share everything(Diskless NFS)

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Node Network Configuration Composition

• Single access point vs Multiple access points
• NIS
• rsh

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Parallel Configuration Composition

• Linux Cluster?? ?? ????? ????
• Message passing
• LAM(Local Area Multi-computer)
• ???? Size? ?? ????? ??.
• ?? Size? ??
• MPICH(MPI-Chameleon)
• ? Size? ??
• PVM(Prallel Virtual Machine)
• KMPI(Kool MPI)

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MPI Linux Cluster Programming

• Parallel Programming
• MPI Programming
• MPI Function
• MPI Programming? ?? ??
• ??? MPI Programming ??

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Parallel Programming

• ?? ????? ??
• PRAM (Parallel Random Access Machine) Model
• QSM (Queued Share Momory) Model
• DMM (Distributed Memory Model)
• Postal Model (Explicit massage passing Model)
• BSP (Bulk Synchronous Parallel)
• HMM (Hierachial Memory Model)
• more

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Parallel Programming(cont.)

• Message passing
• ??? Local ??? ?? ???? ??? ?? ???? ??? ?? ???? ???
  ????, ?? ???? ??? non-local ??? ??? ?, message?
  ?? ??? ??
• ?? ???? ??
• ??? ?? ?? ??? ??? ??
• PVM (Parallel Virtual Machine)
• MPI (Massage Passing Interface)
• BSP (Bulk Synchronus Parallel)

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Parallel Programming(cont.)

• Data Parallel
• ???? ??? ?? ???? ??? ??? ?, ??? ??? ??? Local
  ???? non-local ???? ??? ??? ????? ????? ??
• ?? ???? ??? ??
• Lock-unlock mechanism
• Open_MP
• HPF
• F90
• In-between
• Linda

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MPI Programming

• ??
• 1994? MPI forum? ?? ??? ?
• MPI forum ??? ?? ???? ??? ????? ???? ???? ????
  ??? ?? ??? ??? ???? ?? ??? ??
• Message passing paradigm? ???? ???? ?????? ????
  ??? ??
• ????? industry? de facto ?? ??
• ?? ??? ????? ????? ?? ????? ???? ?? ??
• ?? ??? ??? ?? ??? Architecture??? Open_MP?? ??
  ??? ??? ???? ??? ?

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MPI Programming(cont.)

• ??
• ??? ?? ??? ?? ???? ???(Portability)
• ???(Effichiency)? ?? ??
• ???? ???(Functionality)
• ??
• Message passing standard Portability
• Based on previous message passing libraries
• Program interface
• Allow efficient communication
• Allow heterogeneous environment
• C and Fortran 77 binding language independent
  semantics

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MPI Function

• Task management
• MPI_Init()
• MPI_Barrier()
• MPI_Wtime(), MPI_Wtick()
• MPI_Finalize()
• Communicator
• MPI_Comm_create()
• MPI_Comm_rank()
• MPI_Comm_size()

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MPI Function(cont.)

• Topology management
• MPI_Cart_create()
• MPI_Cart_coords()
• MPI_Cart_get()
• MPI_Cart_rank()
• Communication
• Blocked send-receive MPI_Send(), MPI_Recv(),
  MPI_Sendrecv()
• Non-blocked send-receive MPI_Isend(),
  MPI_Irecv(), MPI_Wait()
• Collective communication MPI_Reduce(),
  MPI_Allreduce(), MPI_Bcast(), MPI_Scatter(),
  MPI_Gather()

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MPI Function(cont.)

• Derived Data type
• MPI_Type_commit()
• MPI_Type_size()
• MPI_Type_struct()
• Process group

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MPI Programming? ?? ??

• Load balance or domain decompostion
• Surface-to-Volume ratio
• Deadlock and racing condition
• ?????? ??? ?? ?? ????? ???? ?? ??
• ?? ?? ? ???? ??? ???? ??
• ??? ?????? ?? ?? ???? ??(???? ?????? ???
  template? ?? ?? debugging? ??)
• ???? ???? ??? ???? ??? ??, ???? ??? message
  passing? ??? ??? ???? ? ??? ???? ??

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MPI Programming? ?? ??

• ?????? ??? ?? ?? ????? ???? ??
• ?? ?? ? ???? ??? ?????? ??? ??
• ?? ?? ??? ??? ???? ??? ??
  (ever dimiinishing returns)
• Message passing? ??? ??? ???? ???
• ???? ???? ????? ?? ?? ???
• ???

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??? MPI Programming ??

• include ltstdio.hgt
• include lt/usr/local/lam-CFC/h/mpi.hgt
• define N 1000000
• main (int argc, char argv)
• int i, node, numtask, subN, iroot
• float AN
• double sum, sumt
• MPI_Init(argc, argv)
• MPI_Comm_rank(MPI_COMM_WORLD, node)
• MPI_Comm_size (MPI_COMM_WORLD, numtask)
• subN N/numtask

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??? MPI Programming ??

• for (i 0 i lt subN i) Ai (float)(i 1
  nodesubN)
• sum 0.0
• sumt 0.0
• iroot 0
• for (i 0 i lt subN i) sum sum Ai
• MPI_Reduce(sum, sumt, 1, MPI_DOUBLE, MPI_SUM,
  iroot,
• MPI_COMM_WORLD)
• printf(total sum f\n, sumt)
• MPI_Finalize()