Program.cs

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System;
using System.Collections.Generic;
using System.Linq;

namespace ConsoleApp66
{
    class Program
    {
        static void Main(string[] args)
        {
            BenchmarkRunner.Run<Tests>();
        }
    }

    [MemoryDiagnoser]
    public class Tests
    {
        static List<Guid> _sourceList;
        static Queue<Guid> _sourceQueue;
        static List<Guid> _list = new List<Guid>();
        static Queue<Guid> _queue = new Queue<Guid>();
        [GlobalSetup]
        public static void GlobalSetup()
        {
            _sourceList = new List<Guid>();
            _sourceQueue = new Queue<Guid>();
            var i = 10_000;
            while (--i >= 0)
            {
                var item = Guid.NewGuid();
                _sourceList.Add(item);
                _sourceQueue.Enqueue(item);
            }
        }

        [Benchmark(Baseline = true)]
        public List<List<Guid>> AsList()
        {
            var target = _list;
            target.AddRange(_sourceList);

            var chonk = new List<List<Guid>>();
            do
            {
                var list = target.Take(900).ToList();
                chonk.Add(list);
                target.RemoveRange(0, list.Count);
            } while (target.Any());
            return chonk;
        }

        [Benchmark]
        public List<List<Guid>> AsQueue()
        {
            var target = _queue;
            for (var i = 0; i < _sourceList.Count; i++)
            {
                target.Enqueue(_sourceList[i]);
            }

            var chonk = new List<List<Guid>>();
            do
            {
                var list = new List<Guid>(900);
                while (list.Count < 900 && target.TryDequeue(out var item))
                {
                    list.Add(item);
                }
                chonk.Add(list);
            } while (target.Any());
            return chonk;
        }
    }
}