Re: Disk write cache (Was: Hyper-Threading Vulnerability)

From: Alan Cox
Date: Mon May 16 2005 - 09:58:00 EST


On Sul, 2005-05-15 at 16:00, Mikulas Patocka wrote:
> There are rumors that some disks ignore FLUSH CACHE command just to get
> higher benchmarks in Windows. But I haven't heart of any proof. Does
> anybody know, what companies fake this command?

The specification was intentionally written so that his command has to
do what it is specified to or be unknown and thus error and not be in
the ident info.

That was done by people who wanted to be very sure that any vendor who
tried to shortcut the command would have "sue me" written on their
forehead.

There are problems with a few older drives which have a write cache but
don't support cache commands.

Alan

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