Clément Grégoire @lectem

Mostly moved to the place where the sky is blue. Performance, GPU APIs, multithreading and game engines specialist @siliceum. Does reverse engineering for fun. lectem.github.io Clermont-Ferrand, France Joined August 2014

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Clément Grégoire @lectem

10 months ago

So in the end, it seems that it was indeed some Minifilter that caused CreateFile to be so slow on PC. (Corporate Security software it seems). But this doesn't explain the issues seen on console... Perhaps it's not optimized for this at all since games tend to have big files ?

Clément Grégoire @lectem

10 months ago

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Clément Grégoire @lectem

10 months ago

Damn, this sounds bad, as in "we have a process doing some heavy polling to see if someone drags and drops and eating CPU/blocking a core mutex" somewhere. Would love to see an ETL trace, but that's one reason why I'm still in Win10.

Vv @ItsJustVV

10 months ago

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Clément Grégoire @lectem

10 months ago

Fixed it: Most folks don't even know what a profiler is.

Simplex @simplex_fx

10 months ago

Fixed it: Most folks don't even know what a profiler is.

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Clément Grégoire @lectem

11 months ago

If you are interested in the challenges of new CPUs, have a look at this talk! (especially the 2nd half related to NUMA, which I predict will be the most challenging)

C++Now @cppnow

a year ago

If you are interested in the challenges of new CPUs, have a look at this talk! (especially the 2nd half related to NUMA, which I predict will be the most challenging)

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Clément Grégoire @lectem

11 months ago

I'm starting to slowly see loss of performance related to using `null` instead of `undefined` in @typescript. Given how much those constructs are used everywhere in the ecosystem, it's death by thousand cuts. (our JS engine is without JIT, no opt here) typescriptlang.org/play/?#code/C4…

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Radek Jurga @poyepolomix

11 months ago

@_plop_ It's not very reliable generally. For waiting, one option is to use CreateWaitableTimerExW with the CREATE_WAITABLE_TIMER_HIGH_RESOLUTION flag.

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Clément Grégoire @lectem

11 months ago

Note to myself (again) : If your GPU shows abnormal timings, check your VRAM usage and find the leaking culprit using process Explorer.

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Kaze Emanuar @KazeEmanuar

a year ago

Turns out EVERYONE WAS WRONG about N64 performance bottlenecks for 28 years. It's not fillrate or memory throughput. At this point, my N64 game is so memory/rdp optimized, that it's actually RSP that is holding up the whole operation.

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Clément Grégoire @lectem

12 months ago

Hey perf Xitter! I am setting up a list for software performance ! Focusing on accounts that talk mostly about performance, not politics or cats, even though I like cats ;) Who do you think is missing ? Don't hesitate to subscribe to it ! x.com/i/lists/183179…

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Daniel Lemire @lemire

a year ago

Measure, measure and measure again. Too often I encounter programmers who argue about software performance. That’s about as useful as arguing that your code must be correct. It is not nothing but computer systems are complex. You may think that you have everything figured…

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Clément Grégoire @lectem

a year ago

@SheriefFYI This is also why for some games, older CPUs with less cores and better single core perf wins, even if the engine usually shows very good core scaling. Amdahl law's a bitch.