The Computer Language
Benchmarks Game

C# .NET Core versus Java fastest programs

Back in April 2010, Russ Cox charitably suggested that only fannkuch-redux, fasta, k-nucleotide, mandlebrot, nbody, reverse-complement and spectral-norm were close to fair comparisons. As someone who implemented programming languages, his interest was "measuring the quality of the generated code when both compilers are presented with what amounts to the same program."

Differences in approach - to memory management, parallel programming, regex, arbitrary precision arithmetic, implementation technique - don't fit in that kind-of fair comparison — but we still have to deal with them.

These are only the fastest programs. There may be additional measurements for programs which seem more-like a fair comparison to you. Always look at the source code.

regex-redux
source secs mem gz busy cpu load
C# .NET Core 2.17 267,768 1869 4.26 36% 30% 84% 46%
Java 10.31 644,560 740 31.47 72% 72% 92% 70%
spectral-norm
source secs mem gz busy cpu load
C# .NET Core 2.14 36,360 764 8.11 93% 98% 95% 93%
Java 4.19 36,680 950 16.31 98% 97% 97% 98%
k-nucleotide
source secs mem gz busy cpu load
C# .NET Core 5.74 183,856 2044 18.58 81% 92% 77% 73%
Java 9.33 447,976 1812 29.36 73% 83% 82% 77%
pidigits
source secs mem gz busy cpu load
C# .NET Core 2.11 36,632 973 2.21 99% 2% 1% 3%
Java 3.07 39,320 938 3.31 2% 5% 3% 98%
binary-trees
source secs mem gz busy cpu load
C# .NET Core 6.05 1,030,984 767 21.45 92% 88% 89% 86%
Java 8.32 953,620 835 28.37 95% 87% 81% 77%
fasta
source secs mem gz busy cpu load
C# .NET Core 1.70 84,508 1691 6.36 95% 92% 90% 98%
Java 2.22 45,172 2473 5.99 61% 50% 98% 60%
fannkuch-redux
source secs mem gz busy cpu load
C# .NET Core 11.14 31,952 1225 44.17 99% 99% 99% 99%
Java 14.33 34,888 1282 56.56 99% 98% 99% 98%
mandelbrot
source secs mem gz busy cpu load
C# .NET Core 5.60 65,296 816 21.78 96% 97% 99% 96%
Java 6.83 79,108 796 26.86 97% 99% 99% 99%
reverse-complement
source secs mem gz busy cpu load
C# .NET Core 3.11 1,029,996 1621 7.76 75% 95% 41% 38%
Java 3.16 712,368 2183 7.08 65% 47% 42% 70%
n-body
source secs mem gz busy cpu load
C# .NET Core 21.82 33,956 1305 22.24 1% 1% 1% 100%
Java 21.95 35,604 1429 22.75 2% 1% 100% 1%
C# .NET Core

.NET Core SDK 3.0.100
Host Version: 3.0.0; Commit: 95a0a61858
<ServerGarbageCollection>true
<ConcurrentGarbageCollection>true

Java

openjdk 13 2019-09-17
OpenJDK Runtime Environment (build 13+33)
OpenJDK 64-Bit Server VM (build 13+33, mixed mode, sharing)