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GNS3 / dynamips

Dynamips development
GNU General Public License v2.0
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packet transmission rate is limited #46

Open flaviojs opened 10 years ago

flaviojs commented 10 years ago

Packet transmission is limited because:

  1. it's done in the ptask thread (default wait time is 10 ms)
  2. each time a packet transmission task is run, only a limited number of packets is sent (the rest waits for the next run)

    Links:

http://forum.gns3.net/topic10476.html

ikiris commented 10 years ago

I understand you fixed (well patched, it still has issues with pps) the displayed issue by bumping up the effective "tx ring" size to 16 instead of 1 in the specific driver affected, but this model of operation itself will present pathology in a few network designs and features (low protocol timers, bfd, ntp, jitter simulation (this basically creates jitter by design), etc). Would it be possible to make this more realtime as opposed to the current 10ms cycle sleep based queue processing?

flaviojs commented 10 years ago

My intention is to make the emulated behavior closer to the real thing. The fact that it's sharing the single ptask thread is enough to break that. =~~ So far I know some chips send on command, while others do memory polling and others depend on the configuration. I want to read the datasheet of each relevant hardware chip and emulate what they do.