iperf3 reporting 0 bytes of throughput under UDP and high latency conditions

# Context

* Version of iperf3: iperf 3.10.1 (cJSON 1.7.13) Server & Client

* Hardware: Raspberry Pi Model B revision 2 Server & Client

* Operating system (and distribution, if any): 2016-02-03-raspbian-jessie

* Other relevant information (for example, non-default compilers,
libraries, cross-compiling, etc.):
Iperf3 is being used to test across a network of multiple bridges for varying hops from 1-5 to reach the server from the client. The bridges are doing encryption/decryption which adds to the latency and communicating over a wired RF connection. I am using Iperf3 to calculate how the throughput varies over differing hop counts, packet sizes and RF channels. The issue looks similar to https://github.com/esnet/iperf/issues/905.

# Bug Report

* Expected Behavior
Seeing current bitrate in all 1 second reports
* Actual Behavior
Depending on latency, I am seeing 0.00 Kbits/sec, 0.00 Bytes transfered for 1s reports until seeing some data.
**Server**
`sudo iperf3 -s -p 2303 -f k`
>-----------------------------------------------------------
>Server listening on 2303 (test #1)
>-----------------------------------------------------------
>Accepted connection from 192.168.105.2, port 52834
>[ 5] local 192.168.100.2 port 2303 connected to 192.168.105.2 port 33650
>[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
>[ 5] 0.00-1.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 1.00-2.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 2.00-3.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 3.00-4.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 4.00-5.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 5.00-6.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 6.00-7.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 7.00-8.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 8.00-9.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 9.00-10.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 10.00-11.00 sec 192 Bytes 1.54 Kbits/sec 1.189 ms 22/25 (88%)
>[ 5] 11.00-12.00 sec 0.00 Bytes 0.00 Kbits/sec 1.189 ms 0/0 (0%)
>[ 5] 12.00-13.00 sec 3.06 KBytes 25.1 Kbits/sec 35.873 ms 21/70 (30%)
>[ 5] 13.00-14.00 sec 3.38 KBytes 27.6 Kbits/sec 10.917 ms 1614/1668 (97%)
>[ 5] 14.00-14.65 sec 1.88 KBytes 23.6 Kbits/sec 433.703 ms 16337/16367 (1e+02%)
>- - - - - - - - - - - - - - - - - - - - - - - - -
>[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
>[ 5] 0.00-14.65 sec 8.50 KBytes 4.75 Kbits/sec 433.703 ms 17994/18130 (99%) receiver

**Client**
`ping 192.168.100.2`
>PING 192.168.100.2 (192.168.100.2) 56(84) bytes of data.
>64 bytes from 192.168.100.2: icmp_seq=1 ttl=62 time=178 ms
>64 bytes from 192.168.100.2: icmp_seq=2 ttl=62 time=180 ms
>64 bytes from 192.168.100.2: icmp_seq=3 ttl=62 time=179 ms
>64 bytes from 192.168.100.2: icmp_seq=4 ttl=62 time=185 ms
>64 bytes from 192.168.100.2: icmp_seq=5 ttl=62 time=179 ms
>64 bytes from 192.168.100.2: icmp_seq=6 ttl=62 time=185 ms
>^C
>--- 192.168.100.2 ping statistics ---
>6 packets transmitted, 6 received, 0% packet loss, time 5006ms
>rtt min/avg/max/mdev = 178.648/181.499/185.372/2.815 ms

`sudo /usr/local/bin/iperf3 -c 192.168.100.2 -t 10 -p 2303 -u -l 64 -f 'k'`
>Connecting to host 192.168.100.2, port 2303
>[ 5] local 192.168.105.2 port 33650 connected to 192.168.100.2 port 2303
>[ ID] Interval Transfer Bitrate Total Datagrams
>[ 5] 0.00-1.00 sec 128 KBytes 1048 Kbits/sec 2047
>[ 5] 1.00-2.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 2.00-3.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 3.00-4.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 4.00-5.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 5.00-6.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 6.00-7.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 7.00-8.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 8.00-9.00 sec 128 KBytes 1049 Kbits/sec 2048
>[ 5] 9.00-10.00 sec 128 KBytes 1049 Kbits/sec 2048
>- - - - - - - - - - - - - - - - - - - - - - - - -
>[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
>[ 5] 0.00-10.00 sec 1.25 MBytes 1049 Kbits/sec 0.000 ms 0/20479 (0%) sender
>[ 5] 0.00-14.65 sec 8.50 KBytes 4.75 Kbits/sec 433.703 ms 17994/18130 (99%) receiver
>
>iperf Done.

and other times it fails to show anything at all
**Server**
>Accepted connection from 192.168.105.2, port 52836
>[ 5] local 192.168.100.2 port 2303 connected to 192.168.105.2 port 45091
>[ ID] Interval Transfer Bitrate Jitter Lost/Total Datagrams
>[ 5] 0.00-1.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 1.00-2.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 2.00-3.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 3.00-4.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 4.00-5.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 5.00-6.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 6.00-7.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 7.00-8.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 8.00-9.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 9.00-10.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 10.00-11.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 11.00-12.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 12.00-13.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 13.00-14.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 14.00-15.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 15.00-16.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 16.00-17.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 17.00-18.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 18.00-19.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 19.00-20.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 20.00-21.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 21.00-22.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 22.00-23.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 23.00-24.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 24.00-25.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 25.00-26.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 26.00-27.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 27.00-28.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 28.00-29.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>[ 5] 29.00-30.00 sec 0.00 Bytes 0.00 Kbits/sec 0.000 ms 0/0 (0%)
>iperf3: error - unable to receive control message: Connection reset by peer

**Client**
`sudo /usr/local/bin/iperf3 -c 192.168.100.2 -t 10 -p 2303 -u -l 64 -f 'k'`
>Connecting to host 192.168.100.2, port 2303
>iperf3: error - unable to read from stream socket: Resource temporarily unavailable

* Steps to Reproduce
Run Iperf3 Server and client with UDP. Set connection between server and client with high latency. As the number of hops/latency increases, The more likely I am to see the "error - unable to read from stream socket: Resource temporarily unavailable". Issue occurs the same if -t is increased from default.

* Possible Solution