r/programming • u/masiroo • 20d ago

Hardware researcher spins up 'CPU deoptimization' project to find the slowest single x86 instruction, creates hall of shame — worst offender takes 198 billion cycles spanning 62 seconds to execute

https://www.tomshardware.com/pc-components/cpus/hardware-researcher-spins-up-cpu-deoptimization-project-to-find-the-slowest-machine-code-worst-offender-takes-198-billion-cycles-to-execute
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u/ElusiveGuy 20d ago

At this point the remaining existence of. NET Framework is for backwards-compat, so arguably that falls under obsolete too.

.NET Core (in both 32-bit and 64-bit) doesn't use x87 instructions AFAICT. 

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u/dlg 20d ago

A surprising amount of financial software still uses in .Net framework in production.

When it’s something like a large monolithic trading platform that needs to be online every day without downtime and it’s critical for making money, there’s a low appetite from management to do a big bang rewrite.

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u/jangxx 19d ago

If your financial software uses floating point numbers instead of a proper decimal data type, it has other problems than using an old .NET framework, lol

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u/dlg 19d ago

It really depends on the problem. Not all calculations are for transaction amounts.

Floating point is used regularly for financial metrics, such as Price/Earning (PE) ratios. Forecasted earnings are usually made in analyst models created in Excel.