RHEL-RT NetworkDeterminismHowto

From RHEL-RT

Jump to: navigation, search
[edit]

Network Determinism - HOWTO

[edit]

TCP

TCP's job is to add latency

  • To obtain effeciency
  • Congestion control
  • Reliable delivery


  • Do you need ordered delivery?
  • Do you need retransmissions? Is it worth destroying throughput for one lost packet?
  • Packet loss can be ok – retransmit might be worse than loss
  • If you must use TCP, turn off Nagle (“the bus doesn't leave until it's full”)

use TCP_NODELAY on your socket

  • Add in info about possibly doing interrupt binding of the nic along with the application recieving packets?
[edit]

Network

  • Interrupt coalescing
    • Ethtool -C
  • Speed of light
    • Use wormholed (blackholes have side effects)
  • Queuing on switches
  • Congestion
    • 802.3x back pressure on speed changes
    • Ethtool -A can be used for band aid
  • Infiniband
    • IP over IB
    • RDMA
  • Have you done netstat -s?
Retrieved from "http://rt.et.redhat.com/page/RHEL-RT_NetworkDeterminismHowto"
Personal tools