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Use clock_gettime on all MacOS after 10.11 - #2341
nicholasjng wants to merge 3 commits into
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| (static_cast<double>(ts.tv_nsec) * 1e-9); | ||
| } | ||
| DiagnoseAndExit("clock_gettime(CLOCK_MONOTONIC, ...) failed"); | ||
| #elif defined(CLOCK_PROCESS_CPUTIME_ID) && !defined(BENCHMARK_OS_MACOSX) |
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we should just remove this section then i think?
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I think if C++17 is the floor now, which requires macOS 10.14+, it's reasonable to assume clock_gettime to always be available, but I didn't want to break backwards compatibility without confirmation.
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right, but your new check below will use thread_id if the version is older, and if not then it'll fall through to the bottom CLOCK_PROCESS_CPUTIME_ID check (line 216) and use clock_gettime. so i think this section is redundant?
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this block is for ProcessCPUUsage(), line 216 is for ThreadCPUUsage(). could you recheck?
I also think this could be simplified, but we need to untangle the two functions, and I'd like your opinion on whether to drop support for macOS without clock_gettime.
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10 years is plenty of time. i think we can drop support for the older versions.
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nice, i pushed two more commits with the necessary cleanups.
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re: the clang-format failure: the struct declarations were autofixed on |
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`clock_gettime` is available on macOS since 10.12 (September 2016), and noticeably faster than mach's `thread_info`, so use it whenever available. Assisted-By: Codex
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Since we assume that we can access `clock_gettime()` on all supported macOS versions, we can remove the mach thread-info route entirely.
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clock_gettimeis available on macOS since 10.12 (September 2016), and noticeably faster than mach'sthread_info, so use it whenever available.Assisted-By: Codex
From experimentation with scoped pauses in
mew. This cuts around 500ns off the total cost of a pause in Python code.EDIT:
clock_gettimeis available here because of<ctime>, which includes<time.h>on Apple's libc++.