[Bug 214171] [tcp] Out-of-order transmission severely degrades performance

[bugzilla-noreply]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=214171

Hiren Panchasara  changed:

   What|Removed |Added

 CC||hi...@freebsd.org
   Assignee|freebsd-bugs@FreeBSD.org|freebsd-...@freebsd.org

--- Comment #1 from Hiren Panchasara  ---
Yes, you are right. We don't do well with loss in general and ooo packets in
particular. We are trying to fix a bunch of issues around that right now.

Would it be possible to you to test -CURRENT? That should work a little better.

-- 
You are receiving this mail because:
You are the assignee for the bug.
___
freebsd-bugs@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/freebsd-bugs
To unsubscribe, send any mail to "freebsd-bugs-unsubscr...@freebsd.org"

[Bug 214171] [tcp] Out-of-order transmission severely degrades performance

[bugzilla-noreply]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=214171

Bug ID: 214171
   Summary: [tcp] Out-of-order transmission severely degrades
performance
   Product: Base System
   Version: 10.3-RELEASE
  Hardware: Any
OS: Any
Status: New
  Severity: Affects Only Me
  Priority: ---
 Component: kern
  Assignee: freebsd-bugs@FreeBSD.org
  Reporter: noah.bergba...@tum.de

Downloading data from a FreeBSD server over a fast (~700Mbps with 0.1% loss)
internet connection that suffers from a lot of packet reordering, I'm seeing
very bad transmission rates (~4Mbps whereas Linux gets ~40Mbps on the same
connection).

Traffic analysis shows that when the client (Windows in my tests) receives
out-of-order packets, it first sends out SACKs until the missing packet arrives
(usually just ~1ms late). Then it ACKs everything normally.

Linux reacts to this by just carrying on - after all, no packets were dropped.
FreeBSD however appears to react to each SACK immediately and indepentently,
assuming that the late packets were actually lost. Because of that, it
retransmits them and lowers the transmission rate (I tested with several
different congestion control modules and it affects all of them).

-- 
You are receiving this mail because:
You are the assignee for the bug.
___
freebsd-bugs@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/freebsd-bugs
To unsubscribe, send any mail to "freebsd-bugs-unsubscr...@freebsd.org"