Reproducing failure to log large messages using Serilog.Sinks.Grafana.Loki

Logger.cs

using Serilog;
using Serilog.Sinks.Grafana.Loki;

namespace LokiMemoryTest
{
    internal class Logger
    {
        public static ILogger Create()
        {
            return new LoggerConfiguration()
                .WriteTo.GrafanaLoki(uri: "https://XXX",
                    credentials: new LokiCredentials
                    {
                        Login = "XXX",
                        Password = "YYY"
                    },
                    labels: new List<LokiLabel>
                    {
                        new() {Key = "app", Value = "loki-memory-test"},
                        new() {Key = "environment", Value = "test"}

                    })
                .MinimumLevel.Debug()
                .CreateLogger();
        }
    }
}

LoggerTests.cs

using System.Text;
using Serilog;

namespace LokiMemoryTest
{
    internal class LoggerTests
    {
        private readonly int _numMessages;
        private readonly int _messageSize;
        private readonly ILogger _logger;

        public LoggerTests(int numMessages, int messageSize, ILogger logger)
        {
            _numMessages = numMessages;
            _messageSize = messageSize;
            _logger = logger;
        }

        public void Run()
        {
            Console.WriteLine($"Sending {_numMessages} messages of {_messageSize} chars");
            for (var i = 0; i < _numMessages; i++)
            {
                var sb = new StringBuilder();
                for (var count = 0; count < 0x100; count++)
                    sb.Append(Guid.NewGuid().ToString("N"));
                var msg = sb.ToString().Substring(0, _messageSize);
                _logger.Debug($"{msg}");
                Thread.Sleep(10);
            }

            var mem1 = 0L;
            var mem2 = 0L;
            var mem3 = 0L;
            do
            {
                Console.WriteLine($"Waiting for memory to be freed");
                mem3 = mem2;
                mem2 = mem1;
                mem1 = WaitAndCheckMemory(2000);
            } while (mem1 != mem2 || mem1 != mem3);
            Console.WriteLine($"Total memory after GC = {mem1 / 1024} KB");
        }

        private long WaitAndCheckMemory(int waitInterval)
        {
            Thread.Sleep(waitInterval);
            return GC.GetTotalMemory(true);
        }
    }
}

Program.cs

using LokiMemoryTest;

Serilog.Debugging.SelfLog.Enable(Console.Error);

new LoggerTests(1000, 5000, Logger.Create()).Run();