git: kernel - Improve tcp starting window

Matthew Dillon dillon at
Mon Nov 9 16:24:01 PST 2015

commit 5353fab65372e67d7adbd6c4a78c2479399fff26
Author: Matthew Dillon <dillon at>
Date:   Mon Nov 9 16:21:14 2015 -0800

    kernel - Improve tcp starting window
    * The tcp sender inflight management was forcing a starting window that
      was way too small for international connections, causing a bulk fetch
      to take several seconds to ramp up.  This management is enabled by default.
    * Add net.inet.tcp.inflight_start to set the starting window and set the
      default to something more reasonable, 33792.  Inflight management previously
      used net.inet.tcp.inflight_min as the starting value, which was 6144 and
      way too small.
    * This will significantly improve the performance of small fetches, e.g.
      pkg install's, update's, and upgrades, and the performance of small web
      server fetches occuring over high latency connections.
    Reported-by: tuxillo

Summary of changes:
 sys/netinet/tcp_subr.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

DragonFly BSD source repository

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