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win: don't wrap uv_getrusage() times at 24 hours - #5415
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uv_getrusage() and uv_getrusage_thread() ran the CPU time from GetProcessTimes() and GetThreadTimes() through FileTimeToSystemTime() and added up wHour, wMinute and wSecond. That function treats the value as a date, so anything past 24 hours moved into wDay and got dropped: 25 hours of CPU time read as 1 hour. A busy process on a machine with many cores gets there within hours, and the reported time then jumps backwards. Compute the seconds and microseconds from the FILETIME ticks instead. This also stops rounding tv_usec to whole milliseconds.
bnoordhuis
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Nov 6, 2026
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LGTM with a suggestion, and good catch.
Move NSEC_PER_TICK and TICKS_PER_SEC from fs.c to internal.h, and use them in uv__filetime_to_timeval() and its test, so there is one definition.
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uv_getrusage() and uv_getrusage_thread() convert CPU time with FileTimeToSystemTime() and add up wHour, wMinute and wSecond. That function treats the value as a date, so anything over 24 hours moves into wDay and is lost: 25 hours of CPU time reads as 1 hour. A busy process on a many-core machine gets there within hours, and the reported time then jumps backwards.
This computes seconds and microseconds from the FILETIME ticks directly. tv_usec also stops being rounded to whole milliseconds.
A test can't burn 24 hours of CPU, so the conversion is a small inline helper in internal.h and the new test checks that. With the old conversion in the helper it fails with
tv.tv_sec == sec (0 == 86400).