File truncation is slow on Windows

hello, I found that the std::fs::write function is quite slow when writing to the same file, I was very surprised why this is so and then I used open options and found that if I put truncate true then that was the cause of the slowdown and then I created a function where I changed the length of the file only at the end after writing, but only if the new length of the data was smaller than the original file size, and therefore I want to ask if it is possible to apply something like this in the std::fs::write method?

Start with the std::fs::write entry point and the OpenOptions behavior described in the issue, reproducing the truncation slowdown on Windows. Compare the current write-and-truncate behavior with the proposed delayed length change, then identify the relevant Rust tests or implementation locations. Done means the behavior is evaluated and any change preserves correct final file contents and length.