The Performance Impact of C++'s `final` Keyword

Post by mgaunard » Thu, Apr 25, 2024, 8:03 AM UTC

somenameforme wrote: post #379

moring wrote: post #376

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> The second is that I think the saying 'premature optimization is the root of all evil' is the root of all evil. The greater evil is putting a one-sentence quote out of context: """ There is no doubt that the grail of efficiency leads to abuse. Programmers waste enormous amounts of time thinking about, or worrying about, the speed of noncritical parts of their programs, and these attempts at efficiency actually have…

Indeed, but I think even that advice, with context, is pretty debatable. Obviously one should prioritize critical sections, but completely ignoring those "small efficiencies" is certainly a big part of how we got to where we are today in software performance. A 10% jump in performance is huge; whether that comes from a single 10% jump, or a hundred 0.1% jumps - it's exactly the same! So referencing something in parti…

Post by fransje26 » Thu, Apr 25, 2024, 7:38 PM UTC

ijan1 wrote: post #382

fransje26 wrote: post #311

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Is there any logical reason why Clang is 50% slower than GCC on Ubuntu?

Hi, I had a look today because it was bugging me and no one had investigated it, so I created an issue[1] with an explanation. But it basically boils down to uniform_real_distribution having a bunch of uninlined calls to 'logl' when compiled with Clang. Otherwise, Clang beats GCC at least on the configuration I tested. (I am the author of the issue) [1] https://gitlab.com/define-private-public/PSRayTracing/-/issu...

Post by throwaway2037 » Sat, Apr 27, 2024, 7:43 AM UTC

rerdavies wrote: post #258

neonsunset wrote: post #251

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In general purpose scenarios, particularly in codebases which have high amount of abstractions, use ASP.NET Core and EF Core, parse and de/serialize text with the use of JSON, Regex and other options, have network and file IO, and are deployed on many-core hosts/container images. There are a few articles on msft devblogs that cover from-netframework migration to older versions (Core 3.1, 5/6/7): - https://devblogs.mi…

Cheating. All of the 6x performance improvement cases seem to be related to using the .net based Kestrel web server instead of IIS web server, which requires marshalling and interprocess communication. Several of the 2x gains appear to be related to using a different database backend. Claims that regex performance has improved a thousand-fold.... seem more troubling than cause for celebration. Were you not precompili…

    > Were you not precompiling your regex's in the older code? That would be a bug.