On Mar 30, 2007, at 7:49 AM, Jeff Cohen wrote: > Chris Lattner wrote: >>> Use the stat information in the Path object, if it is already >>> obtained. This >>> avoids a call to ::fstat by MappedFile when the file size >>> information was >>> already obtained by the Path object. >>> >> >> Interesting approach. The problem is that fstat is significantly >> faster than stat. How about a new Path::getFileStatusFromFD() >> method, which takes an open file descriptor. If the System >> supports it, it can get status information faster by using it, >> otherwise it falls back to getFileStatus (e.g. if win32 doesn't >> have fstat)? >> >> -Chris >> > > It does, but names it _fstat. I'm not sure it's worth the bother > to cache fstat either. stat is slow because it has to look up the > file path.
fstat is slow because it's a syscall, meaning you have to cross the userspace/kernel boundary. -Chris _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
