BenchmarkDotNet=v0.11.5, OS=Windows 10.0.18362
Intel Core i5-9600K CPU 3.70GHz (Coffee Lake), 1 CPU, 6 logical and 6 physical cores
.NET Core SDK=2.2.300
  [Host]    : .NET Core 2.2.5 (CoreCLR 4.6.27617.05, CoreFX 4.6.27618.01), 64bit RyuJIT
  MediumRun : .NET Core 2.2.5 (CoreCLR 4.6.27617.05, CoreFX 4.6.27618.01), 64bit RyuJIT

Job=MediumRun  Server=True  IterationCount=15  
LaunchCount=1  WarmupCount=10  

Method	Length	Mean	Error	StdDev	Ratio	RatioSD	Gen 0	Gen 1	Gen 2	Allocated
Fill	20	3.604 ns	0.0224 ns	0.0210 ns	0.79	0.00	-	-	-	-
Copy	20	4.545 ns	0.0212 ns	0.0198 ns	1.00	0.00	-	-	-	-
NewArray	20	8.063 ns	0.0259 ns	0.0243 ns	1.77	0.01	0.0008	-	-	48 B
StackAlloc	20	10.795 ns	0.0384 ns	0.0360 ns	2.38	0.01	-	-	-	-
StackAllocWithoutLocalsInit	20	10.890 ns	0.0475 ns	0.0421 ns	2.40	0.01	-	-	-	-
CopyByteLoop	20	11.221 ns	0.0499 ns	0.0443 ns	2.47	0.01	-	-	-	-
ArrayPool	20	37.521 ns	0.0832 ns	0.0779 ns	8.26	0.04	-	-	-	-
SmallBlockMemoryStream	20	56.281 ns	0.2089 ns	0.1954 ns	12.38	0.07	0.0075	-	-	472 B
MemoryStream	20	57.892 ns	0.2554 ns	0.2389 ns	12.74	0.08	0.0056	-	-	352 B
PooledMemoryStream	20	60.027 ns	0.1529 ns	0.1430 ns	13.21	0.07	0.0010	-	-	64 B
Native	20	67.875 ns	0.2979 ns	0.2641 ns	14.94	0.09	-	-	-	-
RecyclableMemoryStream	20	1,593.734 ns	9.5103 ns	8.4306 ns	350.77	2.20	0.0057	-	-	448 B
Fill	10000	82.149 ns	0.1985 ns	0.1857 ns	0.66	0.01	-	-	-	-
Copy	10000	124.164 ns	1.0477 ns	0.9800 ns	1.00	0.00	-	-	-	-
StackAllocWithoutLocalsInit	10000	128.688 ns	0.3868 ns	0.3618 ns	1.04	0.01	-	-	-	-
ArrayPool	10000	154.335 ns	2.3499 ns	2.1981 ns	1.24	0.02	-	-	-	-
Native	10000	207.222 ns	2.5186 ns	2.3559 ns	1.67	0.02	-	-	-	-
StackAlloc	10000	410.791 ns	0.9419 ns	0.8810 ns	3.31	0.03	-	-	-	-
PooledMemoryStream	10000	415.421 ns	4.5877 ns	4.2913 ns	3.35	0.05	0.0010	-	-	64 B
NewArray	10000	618.266 ns	4.8143 ns	4.0202 ns	4.97	0.06	0.1574	-	-	10024 B
SmallBlockMemoryStream	10000	1,345.493 ns	2.7104 ns	2.1161 ns	10.82	0.08	0.2651	0.0019	-	16648 B
RecyclableMemoryStream	10000	1,885.239 ns	12.8539 ns	11.3947 ns	15.18	0.17	0.0057	-	-	448 B
MemoryStream	10000	2,290.672 ns	7.1890 ns	6.3729 ns	18.45	0.17	0.3929	0.0076	-	28816 B
CopyByteLoop	10000	4,997.393 ns	21.4632 ns	20.0767 ns	40.25	0.39	-	-	-	-
Fill	100000	1,651.599 ns	54.3235 ns	50.8143 ns	0.97	0.03	-	-	-	-
Copy	100000	1,709.284 ns	8.6351 ns	8.0773 ns	1.00	0.00	-	-	-	-
ArrayPool	100000	1,995.511 ns	34.3353 ns	32.1172 ns	1.17	0.02	-	-	-	-
StackAllocWithoutLocalsInit	100000	2,015.614 ns	38.3572 ns	35.8793 ns	1.18	0.02	-	-	-	-
Native	100000	2,069.543 ns	19.3944 ns	16.1952 ns	1.21	0.01	-	-	-	-
PooledMemoryStream	100000	3,291.219 ns	13.1741 ns	12.3230 ns	1.93	0.01	-	-	-	64 B
RecyclableMemoryStream	100000	4,555.815 ns	68.5092 ns	64.0836 ns	2.67	0.04	-	-	-	448 B
StackAlloc	100000	5,001.828 ns	23.4092 ns	20.7516 ns	2.93	0.02	-	-	-	-
SmallBlockMemoryStream	100000	10,365.935 ns	400.5115 ns	374.6387 ns	6.06	0.22	2.0447	0.2289	-	131408 B
NewArray	100000	28,097.070 ns	6,823.5906 ns	6,382.7909 ns	16.44	3.74	24.7192	24.7192	24.7192	100024 B
CopyByteLoop	100000	50,431.811 ns	696.0034 ns	651.0421 ns	29.51	0.44	-	-	-	-
MemoryStream	100000	66,288.145 ns	1,440.0600 ns	1,202.5153 ns	38.77	0.65	38.8184	38.8184	38.8184	258277 B