3 ms·
Meanwhile on Win32, GetTickCount performs no system calls at all, simply reading a value from a shared memory page. The operating system is updating that value
by Dwedit 3y ago
Meanwhile on Win32, GetTickCount performs no system calls at all, simply reading a value from a shared memory page. The operating system is updating that value behind the scenes.
- gertop 3y agoThat's also how it worked on the commodore 64 in the 80s.
- wtallis 3y agoThis isn't about performing a syscall to get the time, this is about the kernel handling a syscall and in the process checking the time too many times. And getting the time without a full syscall is hardly unique to Windows. On Linux, that's almost the entire point of the vDSO.
- vrmiguel 3y agoIsn't that the same idea as Linux's vdso? https://man7.org/linux/man-pages/man7/vdso.7.html https://man7.org/linux/man-pages/man7/vdso.7.html