The logs went wild. For the first time, swap executions were logged with a resolution that captured causality. Trade A (14:02:03.123456) happened before Trade B (14:02:03.123455). The system could finally see the order of events.
to provide high-precision system time with a resolution of 100ns. Stack Overflow
: The function GetSystemTimePreciseAsFileTime was written to provide sub-microscopic time stamps ( GetSystemTimeAsFileTime .
if (llBasePerformanceCount == 0) llBasePerformanceCount = liCurrentCount.QuadPart; getsystemtimepreciseasfiletime windows 7 patched
// Calculate elapsed 100-ns intervals since init elapsed = (currentCounter.QuadPart - initialCounter.QuadPart) * 10000000; elapsed = elapsed / freq.QuadPart; // Convert to 100-ns units
This is the most recommended and "proper" approach for . Instead of linking directly to the API, programs can load it dynamically at runtime using GetProcAddress . This allows the application to check whether GetSystemTimePreciseAsFileTime exists in the system's kernel32.dll and fall back to the less precise GetSystemTimeAsFileTime if it does not. Many open-source projects, including Cygwin and TensorFlow, have adopted this strategy to maintain broad compatibility while still taking advantage of high-precision timers on supported systems.
The key innovation of GetSystemTimePreciseAsFileTime is its ability to return with high resolution, not just relative ticks. The logs went wild
| Function | Resolution | Introduced | Underlying Source | |----------|------------|------------|--------------------| | GetSystemTimeAsFileTime | ~10-16 ms | Windows 2000 | System timer interrupt (typically 64 Hz or 1024 Hz) | | GetSystemTimePreciseAsFileTime | <1 µs (usually 100 ns) | Windows 8 | Combined: system time + performance counter | | QueryPerformanceCounter | <1 µs | Windows 2000 | HPET or RDTSC (relative time only) |
When an application compiled for Windows 8 or later calls GetSystemTimePreciseAsFileTime on a vanilla Windows 7 system, the loader fails to resolve the import. The result is a runtime error: "The procedure entry point GetSystemTimePreciseAsFileTime could not be located in the dynamic link library KERNEL32.dll." This prevents modern tools, libraries (e.g., recent versions of Node.js, Python, or custom performance software), or patched binaries from running on Windows 7.
typedef VOID (WINAPI *GetSystemTimePreciseAsFileTimePtr)(LPFILETIME); void MyGetSystemTimePrecise(LPFILETIME lpFileTime) static GetSystemTimePreciseAsFileTimePtr pGetSystemTimePrecise = (GetSystemTimePreciseAsFileTimePtr)GetProcAddress(GetModuleHandleA("kernel32.dll"), "GetSystemTimePreciseAsFileTime"); if (pGetSystemTimePrecise != NULL) // Use native high-precision time on Windows 8/10/11 pGetSystemTimePrecise(lpFileTime); else // Emulate behavior on Windows 7 EmulatePreciseTime(lpFileTime); Use code with caution. 2. Writing the Emulation Algorithm The system could finally see the order of events
For scenarios where you need microsecond precision but cannot rely on GetSystemTimePreciseAsFileTime , a common solution is to implement your own high-resolution timestamp by combining GetSystemTimeAsFileTime (for the absolute, low-resolution wall-clock time) with QueryPerformanceCounter (for high-resolution offsets).
Since there is no system update to install this function, users and developers employ several workarounds:
Right-click the shortcut of the broken application and select .