Hot-swap SATA and atacontrol

Peter Jeremy PeterJeremy at
Wed Aug 3 11:16:30 GMT 2005

On Wed, 2005-Aug-03 10:29:39 +0200, Jeremie Le Hen wrote:
>More seriously, I don't see the point in using sync(8) three times
>consecutively, except that's an indirect method to wait for the disk
>buffers to be flushed before powering down.  Please, correct me if I'm

The response I've seen on the PUPS or TUHS mailing list when this was
asked is (roughly):  The time taken to type sync<cr> three times on
a KSR33 is a good match for the time it takes a PDP-11 to flush its
buffers to a RK05.

There is absolutely no point in typing sync before unmounting
filesystems or halting any modern Unix - they all flush their
buffers as part of the unmount or halt processing.  (And the
invention of of FS_UNCLEAN means that mount and fsck know whether
the filesystem was unmounted cleanly or not).

Peter Jeremy

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