Re: Linux 2.6.29

Linus Torvalds
2009-03-31T22:05:34Z

On Tue, 31 Mar 2009, Alan Cox wrote:
>
> How about the far more regular crash case ? We may be pretty reliable but
> we are hardly indestructible especially on random boxes with funky BIOSes
> or low grade hardware builds.

The regular crash case doesn't need to care about the disk write-cache AT
ALL. The disk will finish the writes on its own long after the kernel
crashed.

That was my _point_. The write cache on the disk is generally a whole lot
safer than the OS data cache. If there's a catastrophic software failure
(outside of the disk firmware itself ;), then the OS data cache is gone.
But the disk write cache will be written back.

Of course, if you have an automatic and immediate "power-off-on-oops",
you're screwed, but if so, you have bigger problems anyway. You need to
wait at _least_ a second or two before you power off.

Linus