Degraded performance when using GRE over tinc

[Guus Sliepen]

On Tue, Apr 29, 2014 at 04:31:26PM +0200, Loic Dachary wrote:

> In a setup where OpenVSwitch is used with GRE tunels on top of an interface
> provided by tinc, I'm experiencing significant performance degradation
> problems (from 100Mb/s down to 1Mb/s in the worst case) and I'm not sure how
> to fix this. The manifestation of the problem is, from the user point of
> view, iperf reports ~100Mb/s and rsync reports ~1Mb/s:

A likely problem is that the GRE tunnel sends packets larger than the PMTU
without the DF bit set, which causes tinc to fragment those packets, which
reduces the effective bandwidth and increases the chance that packets are
dropped. Try setting the MTU of the GRE interface manually to 1400 or even
1300, and see if that makes a difference.

-- 
Met vriendelijke groet / with kind regards,
     Guus Sliepen <guus at tinc-vpn.org>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: Digital signature
URL: <http://www.tinc-vpn.org/pipermail/tinc/attachments/20140429/4cd40a33/attachment.sig>