Re: ide write cache issue? [Re: Something corrupts raid5 disks slightly during reboot]

Ville Herva
2003-11-02T08:28:41Z

On Sat, Nov 01, 2003 at 10:05:31PM -0800, you [Andre Hedrick] wrote:
>
> I added the flush code to flush a drive in several places but it got
> pulled and munged.
>
> The original model was to flush each time a device was closed, when any
> partition mount point was released, and called by notifier.
>
> In a minimal partition count of 1, you had at least two flush before
> shutdown or reboot.
>
> So it was not the code because I fixed it, but then again I am retiring
> from formal maintainership.

Thanks, Andre :(.

As an^Wthe IDE expert, can you clarify a few points:

- How long can the unwritten data linger in the drive cache if the drive
is otherwise idle? (Without an explicit flush and with write caching
enabled.)

I had unmounted the fs an raidstopped the md minutes before the boot.

- Can this corruption happen on warmboot or only on poweroff?

- What kind of corruption can one see the if boot takes place "too fast"
and drive hasn't got enough time to flush its cache?

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