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VERSION:2.0
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SUMMARY:Providing Operating System Support for more Efficient Group Commun
 ication
DTSTART:20090622T161500
DTSTAMP:20260407T020650Z
UID:463d4417a4c0d0374dd2435577cc29e9246463f0235256570ac8f478
CATEGORIES:Conferences - Seminars
DESCRIPTION:Prof. Tim Brecht\, University of Waterloo\, Canada\nSeveral im
 portant Internet-based applications such as audio and video conferencing a
 nd broadcasting\, multiplayer on-line games\, and computer supported coope
 rative work\, are all required to send the same data to multiple recipient
 s.  Without IP-level multicast\, this form of group communication is reali
 zed by unicasting the data to each desired recipient. Although this approa
 ch is portable and easy to implement\, it is extremely inefficient for the
  sending host.\n\nIn this talk\, we briefly describe the evolution of kern
 el-based techniques we have explored to efficiently facilitate unicast sen
 d operations for group communication.  We propose a new system call\, send
 group()\, and experimentally evaluate its performance using micro-benchmar
 ks on three different operating systems.  We then analyze the benefits of 
 using sendgroup() within the popular Helix multimedia server.  We first us
 e use Amdahl's law to compute the expected benefits and then experimentall
 y evaluate the Linux implementation.  Our experiments demonstrate an effic
 iency improvement of 45% in a representative live-broadcasting scenario\, 
 closely matching the expected benefits derived using Amdahl's law.\n\nThis
  is joint work done with Martin Karsten\, Michael Kwok\, Elad Lahav\, Jial
 in Song\, Weihan Wang and Tony Zhao from the University of Waterloo.\n\nTi
 m Brecht's homepage
LOCATION:INM202
STATUS:CONFIRMED
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