.NET Core application on Linux slow to crash the first time - linux

Question

I'm running a .NET Core 2.0 console EXE on Ubuntu 16.04. The application terminates with an unhandled exception - which can be anything, e.g. this is enough:
static void Main(string[] args)
{
throw new ApplicationException("Test .NET core exception.");
}
The first time this happens on a given machine there is noticeable delay (2 seconds or so) between the time it prints
Unhandled Exception: System.ApplicationException: Test .NET core exception.
and the time it prints
Aborted (core dumped)
and the process dies. During this time the process uses all of one CPU. (No core files is actually created.)
If I run the application again there is no such delay any more. What is it doing during that first crash and how do I prevent this delay to let it crash quickly? The delay is only a second for a trivial application that just throws an exception, but can be 20-30 seconds for one that uses a lot of RAM.
Running with /usr/bin/time -v dotnet CoreConsoleApp1.dll the first time:
Unhandled Exception: System.ApplicationException: Test .NET core exception.
at CoreConsoleApp1.Program.Main(String[] args) in CoreConsoleApp1\Program.cs:line 20
Command terminated by signal 6
Command being timed: "dotnet CoreConsoleApp1.dll"
User time (seconds): 0.04
System time (seconds): 0.02
Percent of CPU this job got: 1%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:05.92
Average shared text size (kbytes): 0
Average unshared data size (kbytes): 0
Average stack size (kbytes): 0
Average total size (kbytes): 0
Maximum resident set size (kbytes): 32388
Average resident set size (kbytes): 0
Major (requiring I/O) page faults: 193
Minor (reclaiming a frame) page faults: 2708
Voluntary context switches: 1358
Involuntary context switches: 29
Swaps: 0
File system inputs: 57736
File system outputs: 0
Socket messages sent: 0
Socket messages received: 0
Signals delivered: 0
Page size (bytes): 4096
Exit status: 0
The second time:
Unhandled Exception: System.ApplicationException: Test .NET core exception.
at CoreConsoleApp1.Program.Main(String[] args) in CoreConsoleApp1\Program.cs:line 20
Command terminated by signal 6
Command being timed: "dotnet CoreConsoleApp1.dll"
User time (seconds): 0.03
System time (seconds): 0.00
Percent of CPU this job got: 26%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.16
Average shared text size (kbytes): 0
Average unshared data size (kbytes): 0
Average stack size (kbytes): 0
Average total size (kbytes): 0
Maximum resident set size (kbytes): 29416
Average resident set size (kbytes): 0
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 2413
Voluntary context switches: 26
Involuntary context switches: 33
Swaps: 0
File system inputs: 0
File system outputs: 0
Socket messages sent: 0
Socket messages received: 0
Signals delivered: 0
Page size (bytes): 4096
Exit status: 0
The project was built in Visual Studio 2017 on Windows.
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.4 LTS
Release: 16.04
Codename: xenial
$ uname -a
Linux evgeny-linux 4.4.0-1052-aws #61-Ubuntu SMP Mon Feb 12 23:05:58 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux
$ cat /proc/sys/kernel/core_pattern
|/usr/share/apport/apport %p %s %c %d %P