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<DIV>In a message dated 1/14/2007 9:01:38 P.M. Central Standard Time,
hmh@debian.org writes:</DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>It has
been doing dumb things like this for a long time now. It was a
MAJOR<BR>stupid mistake to ever try to work around this on userspace
(userspace<BR>simply does not know enough to get it right always, and it
simply *cannot*<BR>do it in suspend-to-disk, and other corner cases), and it
will take two or<BR>three years before we manage to fix it and remove the "do
it in userspace by<BR>default" crap halt(8) has to carry
around.<BR></FONT></BLOCKQUOTE></DIV>
<DIV></DIV>
<DIV>I agree heartily, userspace ought provide the 'why', the kernel the 'how'
and 'when'. </DIV>
<DIV> </DIV>
<DIV>There isn't anything in '/sbin/halt' that might not better be a boot up
parameter with defaults, and 'halt' just reduced to a stub that forces parameter
changes if need be then makes one OS call.</DIV>
<DIV> </DIV>
<DIV>File systems ought to know to flush their caches and otherwise handle
shutdown/restart/sleep/resume.</DIV>
<DIV> </DIV>
<DIV>Block device drivers should be smart enough to sync on their own when idle
for more than a minute, and if necessary on all warnings of power / bootup state
changes.</DIV>
<DIV> </DIV>
<DIV>Though new to linux, is there no little pool of 'kernel worker
threads' that drains a 'to do' queue? I sense the 'resort to user space'
might have its roots there, a desire for non-blocking or parallelism in these
system state change tasks.</DIV>
<DIV> </DIV>
<DIV>Harry Coin</DIV>
<DIV> </DIV>
<DIV> </DIV>
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