Speed issue in only one direction

[Florent Bautista]

Hi all,

I'm back again with my speed issues. The past issues where dependant of
network I used.

Now I run my tests in a lab, with 2 configurations linked by a Gigabit
switch :

node1: Intel Core i5-2400 with Debian 7.2
node2: Intel Core i5-3570 with Debian 7.2

Both have AES and PCLMULQDQ announced in /proc/cpuinfo.

I use Tinc 1.1 from Git.

When I run an iperf test from node2 (client) to node1 (server) with
default options, I have 600+ Mbit/s.
When I run an iperf test from node1 (client) to node2 (server) with
default options, I have 300 Mbit/s MAX.

The strange thing is that 300 Mbit/s was the limit with Tinc 1.0.

I checked twice, both of nodes are now running tinc 1.1...
Of course, when I do iperf without Tinc, I have 1 Gbit/s...

sptps_speed report correct speeds (node1 is less powerfull than node2) :

root at node1:~# sptps_speed
Generating keys for 10 seconds:            597.41 op/s
ECDSA sign for 10 seconds:                 549.90 op/s
ECDSA verify for 10 seconds:               470.60 op/s
ECDH for 10 seconds:                       277.88 op/s
SPTPS/TCP authenticate for 10 seconds:     132.38 op/s
SPTPS/TCP transmit for 10 seconds:           5.18 Gbit/s
SPTPS/UDP authenticate for 10 seconds:     131.75 op/s
SPTPS/UDP transmit for 10 seconds:           5.45 Gbit/s


root at node2:~# sptps_speed
Generating keys for 10 seconds:            698.60 op/s
ECDSA sign for 10 seconds:                 657.31 op/s
ECDSA verify for 10 seconds:               556.76 op/s
ECDH for 10 seconds:                       329.52 op/s
SPTPS/TCP authenticate for 10 seconds:     156.73 op/s
SPTPS/TCP transmit for 10 seconds:           6.19 Gbit/s
SPTPS/UDP authenticate for 10 seconds:     157.53 op/s
SPTPS/UDP transmit for 10 seconds:           6.37 Gbit/s


What could be the cause of this ?