Linus Torvalds writes: (Summary) At least fork(), for example, only clears the dirty bit,
doesn't mark it write-protected.
doesn't mark it write-protected.
So there is some rate-limiting of dirty pages, but I do not believe that we've ever really *serialized* writes.
that we've ever really *serialized* writes.
I don't think that what you are doing is necessarily wrong, I'm just pointing out that you may still see mmap'ed pages being modified concurrently with the actual IO, and that this will potentially mean (for example) that things like checksums won't be reliably unless you do the checksum as you copy the data to a network packet or something.
doesn't mark it write-protected.
So there is some rate-limiting of dirty pages, but I do not believe that we've ever really *serialized* writes.
that we've ever really *serialized* writes.
[...]
than writing only whole pages.I don't think that what you are doing is necessarily wrong, I'm just pointing out that you may still see mmap'ed pages being modified concurrently with the actual IO, and that this will potentially mean (for example) that things like checksums won't be reliably unless you do the checksum as you copy the data to a network packet or something.