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Re: Proposal: B_ARRIER (addresses wapbl performance?)

On Wed, Oct 29, 2008 at 08:57:16PM -0500, David Young wrote:
> [...]
> Are there IDE disks that support neither FUA nor cache flush?
> It seems that IDE disks on a USB-IDE adapter may fit this description.

Some disks may not support it. cache flush support was made mandatory in
ATA-4 (from memory). that's why I added a 2 seconds delay in reboot(9)
before triggering the hardware reset or poweroff: wd_flushcache() wouldn't
work on my root drive and the / superblock would always be marked dirty.

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference

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