Re: scsi vs ide performance on fsync's

David Balazic
2001-03-07T12:49:01Z

Andre Hedrick (andre@linux-ide.org) wrote on Wed Mar 07 2001 - 01:58:44 EST :

> On Wed, 7 Mar 2001, Jonathan Morton wrote:

[ snip ]

> > >Since all OSes that enable WC at init will flush
> > >it at shutdown and do a periodic purge with in-activity.
> >
> > But Linux doesn't, as has been pointed out earlier. We need to fix Linux.
>
> Friend I have fixed this some time ago but it is bundled with TASKFILE
> that is not going to arrive until 2.5. Because I need a way to execute
> this and hold the driver until it is complete, regardless of the shutdown
> method.

I don't understand 100%.
Is TASKFILE required to do proper write cache flushing ?

> > >Err, last time I check all good devices flush their write caching on their
> > >own to take advantage of having a maximum cache for prefetching.
> >
> > Which doesn't work if the buffer is filled up by the OS 0.5 seconds before
> > the power goes.
>
> Maybe that is why there is a vender disk-cache dump zone on the edge of
> the platters...just maybe you need to buy your drives from somebody that
> does this and has a predictive sector stretcher as the energy from the
> inertia by the DC three-phase motor executes the dump.

So where is a list of drives that do this ?
www.list-of-hardware-that-doesnt-suck.com is not responding ...

> Ever wondered why modern drives have open collectors on the databuss?

no :-)

--
David Balazic
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"Be excellent to each other." - Bill & Ted
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