What does sync() _really_ do?

[Kristoffer Eriksson]

In article <5156 at segue.segue.com> jim at segue.segue.com (Jim Balter) writes:
>While there may a such a sync queue in some kernel somewhere, there isn't one
>in any of the common kernels that have had triple syncs directed at them.

When I type "sync" once after some disk writing activity on my system,
there is a delay before I get the prompt back. If that delay is not caused
by sync() waiting for disk blocks to be written, then I wonder what it is
caused by. How do your systems act? Do they give you any delay?
-- 
Kristoffer Eriksson, Peridot Konsult AB, Hagagatan 6, S-703 40 Oerebro, Sweden
Phone: +46 19-13 03 60  !  e-mail: ske at pkmab.se
Fax:   +46 19-11 51 03  !  or ...!{uunet,mcsun}!sunic.sunet.se!kullmar!pkmab!ske