Some messages show up in Wireshark, but are not captured by Kiwi Syslog

Hello,

I am testing Kiwi Syslog Server 9.5.0.332 with Kiwi Syslog Gen 2.2.0; both are running on separate computers.  On the computer running Kiwi Syslog Server, I am also running Wireshark 1.12.3.

I am trying a single pass of the "500 packet burst every 10 seconds" using UDP as the transport.

Now I understand that UDP is not reliable and that some messages will be lost when performing a burst like this, however I am often seeing that Syslog is only logging a subset of what Wireshark captured.  In one of my tests, Wireshark captured 492 of the syslog packets, while Kiwi Syslog only captured 204.

I repeated this test multiple times.  Sometimes Kiwi Syslog will capture the same number of packets as Wireshark, but more often Kiwi Syslog only captures a subset.

I was expecting that Kiwi Syslog would always capture the same number of syslog packets as Wireshark.  What might be causing this problem?

I attached a filtered version of the Wireshark capture (only UDP packets directed at port 514), and the Syslog capture (in case it helps)

Thanks

Ken