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Microsoft's New 64-Bit Compiler Speeds Up .NET Program Starts

The JIT compiler will also be the new codebase for future compilers across platforms.

Microsoft has released a community technology preview (CTP) of a new 64-bit compiler for the .NET Framework that will become the basis for all its future compilers.

Andrew Pardoe, PM Manager for the CLR Runtime PM team, wrote in a blog post that the new compiler, called RyuJIT (Just-in-time), will eventually replace the current 64-bit JIT compiler, known as JIT64. The new compiler is specifically tuned to compile code quickly, helping programs start up faster.

Pardoe explained the reasoning behind upgrading from the older, slower JIT64:

"The .NET 64-bit JIT was originally designed to produce very efficient code throughout the long run of a server process ...Taking time to compile efficient code made sense when 64-bit was primarily for server code."

But speed is paramount in today's mobile environment, and RyuJIT programs start up to 30 percent faster, Pardoe wrote. He also gave some numbers to bolster his argument. While most programs will compile a bit faster, some will compile exponentially faster. A chart in the blog entry shows that regular expressions (RegEx), for example, struggle mightily with JIT64, so a program like RFC822 e-mail RegEx compiles 32 times faster, simple e-mail RegEx is 21 times faster, and phone RegEx compiles five times faster. "Faster compilation with less memory usage makes everyone's code run better," he blogged.

Performance gains are only one benefit of RyuJIT, Pardoe explained. Currently, it works for the x86 JIT, but in the future it will be the basis for all JIT compilers, including those for ARM, Machine Dependent Intermediate Language (MDIL), and others. The unified codebase will increase code compatibility across platforms, and allow for quicker release of new code features.

RyuJIT is a CTP, and Pardoe warned that it's not for production environments. It works on 64-bit editions of Windows 8.1 and Windows Server 2012 R2. The reason Windows 8.1 was chosen, when most developers aren't using it, was explained by Microsoft's Kevin Frei in answer to comments under the blog:

"We targeted our CTP at Windows 8.1/Windows Server 2012 R2 for strictly tactical reasons: from a code-generation perspective, .NET 4.5.1 that's included in Windows 8.1 is quite different from .NET 4.5.1 for Windows 7/8. In order to reduce our up-front dev & test costs, we decided to focus just on Windows 8.1... When we're ready, it will be part of the full .NET Runtime, fully supported on all platforms that .NET supports."

Not everyone was happy with that answer, however. One, "Carl D", said that "Having it available on Win 8.1 only makes it a non-starter for me."

About the Author

Keith Ward is the editor in chief of Virtualization & Cloud Review. Follow him on Twitter @VirtReviewKeith.

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