Microsoft just announced the public availability of .NET Core 2.1, the latest version of its .NET Core framework. Forget everything else improved in .NET Core 2.1, but one feature is sufficient for you to make a move to .NET Core 2.1, i.e., performance.
.NET Core 2.1 is the fastest .NET framework ever developed. Here are some of the performance improvement benchmarks via blog.
JIT Improvements
There is major improvement in collection classes. Now JIT can statically determine some virtual invocations and there is about 2.5x improvement in performance.
Method .NET Core 2.0 .NET Core 2.1
EqualityComparerInt 32 2.2106 ns 0.8725 ns
DictionaryContainsValue 3.419 us 1.519 us
EnumHasFlag 14.9214 ns/48 B 0.2932 ns/0 B
LoopBodyLayout 56.30 ns 30.49 ns
LoweringTESTtoBT 1.414 ns 1.057 ns
BoxingAllocations 12.444 ns/48 B 1.391 ns/0 B
Threading performance comparison.
Method .NET Core 2.0 .NET Core 2.1
ThreadStatics 7.322 ns 5.269 ns
TimerContention 332.8 ms 135.6 ms
SerialCancellationTokenRegistration 95.29 ns/48 B 62.45 ns/0 B
ParallelCancellationTokenRegistration 31.31 ns 18.19 ns
AsyncMethodAwaitInvocation 20.36 ns/0 B 13.48 ns/0 B
Strings, Formatting, and Other Improvements
Here is a list of some strings and formatting related methods and their performance.
StringIndexOf 41.13 ns 15.94 ns
IndexOfAny 94.66 ns 38.27 ns
StringToLowerChangesNeeded 187.00 ns 96.29 ns
StringToLowerAlreadyCased 197.21 ns 68.81 ns
StringSplit 459.5 ns 305.2 ns
StringConcatCharEnumerable 22.05 us 15.56 us
StringFormat 196.1 ns 151.3 ns
StringBuilderAppend 6.523 ms 3.268 ms
Int32Formatting 65.27 ns 34.88 ns
Int32Parsing 96.95 ns 76.99 ns
DoubleFormatting 448.7 ns 86.8 ns
BigIntegerFormatting 36.677 us 3.119 us
DateTimeOffsetFormatR 220.89 ns 64.60 ns
DateTimeOffsetFormatO 263.45 ns 104.66 ns
ConvertFromBase64String 45.99 us 29.86 us
ConvertFromBase64Chars 46.34 us 29.51 us
EnumerateFiles 638.0 us 539.5 us
DeriveBytes 9.199 ms 8.084 ms
GuidNewGuid 7.179 us 1.770 us
RegexCompiled 473.7 ns 295.2 ns
As you can see from the above table, .NET Core 2.1 is much faster than its predecessor.