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    SubjectRe: [PATCH 1/3] copyfile: generic_sendpage
    On Mon, 6 September 2004 14:45:38 +0200, Gunnar Ritter wrote:
    >
    > It is an even more serious problem in my experience. I have been
    > using sendfile() in my cp command at <http://heirloom.sourceforge.net>
    > for quite some time, and I quickly decided to send files separated in
    > some decently sized blocks. Otherwise if a whole file is sent at once
    > and the source file is e.g. on an uncached floppy disk, cp will become
    > uninterruptible for about a minute, which is a serious usability flaw.
    > The user might discover that he is copying the wrong file, or he might
    > simply change his mind and like to abort the copy or whatever. A
    > performance gain of only 10 % is neglegible in comparison to this
    > problem. Thus I think if copyfile() would not be interruptible by SIGINT
    > and friends, its practical value would be quite limited.

    Using a loop of 4k sendfile commands should be easy enough to do.
    Problem is that copyfile(2) should do some decent cleanup after
    receiving a signal. Hans Reiser got it right that all filesystem
    operations should be atomic.

    Jörn

    --
    Premature optimization is the root of all evil.
    -- Donald Knuth
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