cbench throughput test does not work in Boron

Both plugins (He + Li) show the following:

cbench -c 10.29.8.203 -t -m 12000 -M 10000 -s 8 -l 10

cbench: controller benchmarking tool
running in mode 'throughput'
connecting to controller at 10.29.8.203:6633
faking 8 switches offset 1 :: 10 tests each; 12000 ms per test
with 10000 unique source MACs per switch
learning destination mac addresses before the test
starting test with 0 ms delay after features_reply
ignoring first 1 "warmup" and last 0 "cooldown" loops
connection delay of 0ms per 1 switch(es)
debugging info is off
controller msgbuf_read() = -1: msgbuf_read: Connection reset by peer
... exiting

My interpretation is that controller closes the switches connections and therefore we get following report:

05:52:56.797 8 switches: flows/sec: 0 0 0 0 0 0 0 0 total = 0.000000 per ms
05:53:08.897 8 switches: flows/sec: 0 0 0 0 0 0 20000 0 total = 1.666627 per ms
05:53:20.998 8 switches: flows/sec: 0 0 0 0 0 0 0 0 total = 0.000000 per ms
05:53:33.098 8 switches: flows/sec: 0 0 0 0 0 0 0 0 total = 0.000000 per ms
05:53:45.222 8 switches: flows/sec: 0 0 0 0 0 776 0 0 total = 0.064542 per ms
05:53:57.323 8 switches: flows/sec: 0 0 0 0 0 0 0 0 total = 0.000000 per ms
05:54:09.423 8 switches: flows/sec: 0 0 0 0 0 0 0 0 total = 0.000000 per ms