Nuid

[jasper-d]

Notable changes:

• Created a new Nuid implementation (internal for now) because adapting the existing one w/o introducing breaking changes was not desirable in terms of performance and idiomatic (.NET-ish) interface
• Marked the old implementation as obsolete so it can be removed in a future release
• Removed the different inbox algorithms for old and new requests styles (not sure why the distinction was made)
• Opted to use base-64 instead of base-62 to avoid modulo bias (cf. Modulo bias in prefix generation nuid#15) and gain some performance
• Added a micro benchmark project (uses BenchmarkDotNet) to ensure performance is acceptable (see results below). All performance optimizations are based on evidence provided by benchmark runs.
• Made NATS.Client internals visible to UnitTests and MicroBenchmarks

Let me know if you have questions/change requests

Edit:

Haven't changed the token generation yet (nats-io/nats.net#351 (comment)), would do so in a seperate PR

Issue for reference: #351

Benchmark Results

NextNuid is in this PR, NUIDNext is the existing (unused) NUID implementation, OldNewInbox is the currently used implementation (https://github.com/jasper-d/nats.net/blob/bd2abf39df3b7c7c06d12ec9a0069e066650f504/src/Benchmarks/MicroBenchmarks/Program.cs).

Windows

BenchmarkDotNet=v0.12.0, OS=Windows 10.0.18362
Intel Core i7-4712MQ CPU 2.30GHz (Haswell), 1 CPU, 8 logical and 4 physical cores
.NET Core SDK=3.1.101
  [Host]     : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT
  Job-JHNFEY : .NET Framework 4.8 (4.8.4075.0), X64 RyuJIT
  Job-LNVMVJ : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT

Method	Runtime	Mean	Error	StdDev	Ratio	Gen 0	Gen 1	Gen 2	Allocated
NextNuid	.NET 4.6.2	75.57 ns	0.039 ns	0.035 ns	0.17	0.0459	-	-	144 B
NUIDNext	.NET 4.6.2	454.71 ns	1.150 ns	1.076 ns	1.00	0.0458	-	-	144 B
OldNewInbox	.NET 4.6.2	789.66 ns	0.695 ns	0.616 ns	1.74	0.1040	-	-	329 B
NextNuid	.NET Core 3.1	81.45 ns	0.368 ns	0.344 ns	0.19	0.0458	-	-	144 B
NUIDNext	.NET Core 3.1	436.05 ns	0.296 ns	0.277 ns	1.00	0.0458	-	-	144 B
OldNewInbox	.NET Core 3.1	586.60 ns	0.713 ns	0.667 ns	1.35	0.0706	-	-	224 B

Linux

BenchmarkDotNet=v0.12.0, OS=fedora 31
Intel Core i7-3612QM CPU 2.10GHz (Ivy Bridge), 1 CPU, 8 logical and 4 physical cores
.NET Core SDK=3.1.101
  [Host]     : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT
  Job-AEFKXL : .NET Core 3.1.1 (CoreCLR 4.700.19.60701, CoreFX 4.700.19.60801), X64 RyuJIT

Runtime=.NET Core 3.1

Method	Mean	Error	StdDev	Ratio	Gen 0	Gen 1	Gen 2	Allocated
NextNuid	116.7 ns	0.35 ns	0.33 ns	0.19	0.0458	-	-	144 B
NUIDNext	599.7 ns	0.59 ns	0.52 ns	1.00	0.0458	-	-	144 B
OldNewInbox	761.4 ns	0.62 ns	0.58 ns	1.27	0.0706	-	-	224 B

nuid.go for reference (the figures differ quite a lot between runs, but these are the lowest numbers I got):

[jd@linux]~/sources/nuid.origin%  go test -bench=.

goos: linux
goarch: amd64
BenchmarkNUIDSpeed-8            12650074                91.9 ns/op            32 B/op          1 allocs/op
BenchmarkGlobalNUIDSpeed-8      11843164               101 ns/op              32 B/op          1 allocs/op
PASS
ok      _/home/jd/sources/nuid.origin   6.192s

[ColinSullivan1]

We dove right in making comments before saying thank you for the PR. Just wanted to leave a note saying that this is really good and highly appreciated!

[jasper-d]

Thank you, much appreciated. Comments are fair, so it's all good. :)

[jasper-d]

Sorry, added another commit. Changed most uses of signed integers to unsigned ones. I think this actually improves the code since non-negative integers are expected in multiple places. Also removed a suspicious cast to Int32.

[ColinSullivan1]

LGTM. Thanks!

[ColinSullivan1]

LGTM. Thanks!

[watfordgnf]

For posterity, here are the benchmarks on my workstation:

BenchmarkDotNet=v0.12.0, OS=Windows 10.0.17763.973 (1809/October2018Update/Redstone5)
Intel Xeon Silver 4114 CPU 2.20GHz, 2 CPU, 20 logical and 20 physical cores
  [Host]     : .NET Framework 4.8 (4.8.4075.0), X64 RyuJIT
  Job-OZBAHI : .NET Framework 4.8 (4.8.4075.0), X64 RyuJIT
  Job-MNUBEA : .NET Core 3.1.0 (CoreCLR 4.700.19.56402, CoreFX 4.700.19.56404), X64 RyuJIT

Method	Runtime	Mean	Error	StdDev	Ratio	Gen 0	Gen 1	Gen 2	Allocated
NextNuid	.NET 4.6.2	105.72 ns	0.392 ns	0.367 ns	0.23	0.0229	-	-	144 B
NUIDNext	.NET 4.6.2	462.81 ns	1.806 ns	1.690 ns	1.00	0.0224	-	-	144 B
NextNuid	.NET Core 3.1	92.28 ns	0.558 ns	0.466 ns	0.21	0.0200	-	-	144 B
NUIDNext	.NET Core 3.1	449.42 ns	1.683 ns	1.574 ns	1.00	0.0200	-	-	144 B