Alexandre DENIS - PowerPoint PPT Presentation

Loading...

PPT – Alexandre DENIS PowerPoint presentation | free to view - id: 13ac1d-MTFhY



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Alexandre DENIS

Description:

Meta-communications in component-based communication frameworks for ... INRIA/LaBRI, Bordeaux, France. Alexandre.Denis_at_inria.fr. HPC-GECO, Paris - June 2006 ... – PowerPoint PPT presentation

Number of Views:77
Avg rating:3.0/5.0
Slides: 34
Provided by: Pers62
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Alexandre DENIS


1
Meta-communications in Component-based
Communication Frameworksfor Grids
  • Alexandre DENIS
  • INRIA/LaBRI, Bordeaux, France
  • Alexandre.Denis_at_inria.fr

HPC-GECO, Paris - June 2006
2
Outline
  • Introduction
  • Meta-communications
  • definition
  • goal
  • requirements
  • A flexible approach for meta-communications
  • Implementation in PadicoTM
  • Evaluation
  • Conclusion

3
Context and Goals
  • Network communications on grids

4
The Grid Computer
  • Hierarchical networks
  • WAN Internet, ATM, VTHD (2.5 Gbit/s), etc.
  • LAN Ethernet
  • SAN Myrinet, SCI,InfiniBand
  • Computing resources
  • Clusters of PC
  • Supercomputers
  • Visualization hardware
  • ...
  • Heterogeneity!

SAN
LAN
Homogeneous cluster
WAN
SAN
Homogeneous cluster
Parallel computer
5
Communication schemes
  • Example 1
  • Two clusters connected through a WAN
  • MPI code coupled with CORBA

WAN
SAN
SAN
6
Communication schemes
  • Example 1
  • An MPI code on each cluster (over a SAN)
  • code coupling through CORBA over the WAN

CORBA
MPI
MPI
Firewall
NAT
7
Communication schemes
  • Example 2
  • One MPI communicator spaning accross two clusters

Myrinet
Infiniband
MPI
8
Communication schemes
  • Example 3
  • Computation on a cluster
  • Cluster protected by a firewall
  • Visualization on a dedicated node

CORBA
Visualization
MPI
Laptop with dynamic IP address
Firewall
9
Our Goals
  • Problems raised by communications on grids
  • Connectivity
  • Sites protected by firewalls
  • Non-routed private IP addresses, NAT
  • Security
  • Ensure privacy of transmitted data
  • Protect from intruders
  • Performance
  • Use high-performance networks where available
  • Use WAN-optimized methods where needed
  • e.g. parallel streams when latency x bandwidth is
    high
  • TCP splicing instead of tunneling where possible
  • Component-based communications frameworks are
    designed to reach such a flexibility!

10
Component-based communication framework
  • Components as building blocks for the
    communication stack
  • e.g. Globus XIO, NetIbis, PadicoTM

MPI
CORBA
JVM
DSM
Component-based communication framework
Myrinet
Infiniband
Quadrics
TCP/IP
11
Meta-communications
12
Meta-Communications
  • Establishing data connections requires auxiliary
    communications
  • transmit the assembly description
  • communication methods need brokering, e.g.
  • TCP needs port number exchange
  • TCP splicing needs synchronization
  • Myrinet/Infiniband/... need channel number
    negotiation
  • ...
  • Meta-communications (or control
    communications)

13
Meta-communications example
  • A client connects to a server

TCP port14235
14
Meta-communications example
  • A client connects to a server

15
The weakest link
  • Meta-communications properties determine the
    whole communication framework
  • Connectivity
  • No data connection if no meta-communication
    channel
  • Security
  • Able to connect to meta-communication channel
  • Able to establish data connection with any
    assembly
  • Performance
  • Messaging on meta-communication channel is on
    critical path for data connection establishment
  • Performance of meta-communications limits data
    connection establishment time

16
Do withoutmeta-communications?
  • Try to eliminate the weakest link
  • no brokered communication methods
  • no TCP splicing, no reverse connection
  • needs to use well-known ports
  • no assembly negotiation
  • the server must guess what clients will use!
  • all clients must use the same communication
    method
  • Limited to static communication schemes

17
A flexible approach for meta-communications
  • A two-step bootstrap approach

18
Component-basedmeta-communications
  • Meta-communication channel must meet
    requirements
  • Connectivity
  • Security
  • Performance
  • Idea make the meta-communication channel itself
    component-based
  • Problem needs a meta²-communication channel!
  • meta-communications for the meta-communications

19
Two-step bootstrap
  • Two levels of meta-communications
  • control channel
  • meta-communications for the data channel
  • bootstrap channel
  • meta-communications for the control channel
  • Requirements for the bootstrap channel
  • connectivity security
  • low performance requirements
  • bootstrap channel used only on control channel
    establishment
  • routing is acceptable
  • uses no meta-communications
  • static component stack (no assembly negotiation)

20
Bootstrap example
  • Bootstrap phase 1 establish bootstrap channel
  • a rendez-vous node is listening
  • nodes connect to the rendez-vous node
  • using a secure connection
  • the rendez-vous node routes messages

21
Bootstrap example
  • Bootstrap phase 2 establish control channel
  • use the bootstrap channel for meta-communications
  • establish an optimized control channel

LID0x1234QPN2
22
The PadicoTM Framework
  • Communication framework designed for grids
  • Transparent access to various networks
  • Myrinet, Infiniband, Quadrics, TCP/IP, ...
  • Supports plugable communication methods
  • Supports a wide range of middleware systems
  • MPI, CORBA, SOAP, Java, DSM, HLA

Middleware 1
Middleware 2
Middleware 3
Middleware 4
Method 1
PadicoTM
Method 2
Network 1
Network 2
Network 3
Network 4
23
Implementation in PadicoTM
  • Available communication methods
  • plain TCP, high-performance networks (Myrinet,
    Infiniband, Quadrics, ...), shmem
  • methods for WAN TCP splicing, SOCKS proxy, SSH
    tunneling
  • data filters LZO ZIP compression, Gnu TLS
    security
  • routing
  • Bootstrap connection through TLS/TCP
  • bootstrap through SSH tunnels if rendez-vous node
    is not directly reachable
  • Default configuration for optimized control
    channel

24
Two-step bootstrapoptimization
  • Lazy connections on control channel
  • establish control connection on the first data
    connection establishment
  • reduces application startup time
  • Federation of rendez-vous nodes
  • reduces load on rendez-vous node

25
Evaluation
  • Connectivity
  • succeeds to get all-to-all connectivity in the
    aforementioned cases
  • NAT, private addresses, dynamic IP address (not
    in DNS)
  • firewalls

26
Communication schemes
  • Example 1
  • An MPI code on each cluster (over a SAN)
  • code coupling through CORBA over the WAN

CORBA
MPI
MPI
Firewall
NAT
27
Communication schemes
  • Example 2
  • One MPI communicator spaning accross two clusters

Myrinet
Infiniband
MPI
28
Communication schemes
  • Example 3
  • Computation on a cluster
  • Cluster protected by a firewall
  • Visualization on a dedicated node

CORBA
Visualization
MPI
Laptop with dynamic IP address
Firewall
29
Evaluation
  • Security
  • user-configurable assembly
  • TLS usable for bootstrap/control/data
  • firewall crossing doesn't compromise security
  • encryption/authentication may be given up by users

30
Evaluation
  • Performance
  • high performance networks actually usable for
    control channel and data communications
  • e.g. PadicoTM virtual sockets / Infiniband
  • latency 5.7 usec.
  • bandwidth 708 MB/s
  • connection establishment 30 usec.

31
Conclusion
  • Component-based communication frameworks brings
    the required flexibility for grids
  • require a meta-communication channel
  • Our contribution
  • a flexible approach to meta-communications
  • no compromise regarding connectivity, security
    and performance
  • model actually implemented in PadicoTM
  • code available
  • http//runtime.futurs.inria.fr/PadicoTM/

32
Future works
  • More communication methods
  • e.g. Globus Security Infrastructure (GSI)
  • Large scale experiments
  • test scalability with thousands of nodes
  • Fault-tolerance
  • required for large scale experiments

33
(No Transcript)
About PowerShow.com