Bug#569598: disk caches?

[Philipp Weis <pweis@pweis.com>]

On 2010-02-16 11:21, Christoph Hellwig <hch@lst.de> wrote:
> Do you have disk write caches disabled on the machine?  Neither md, nor
> dm, nor loop pass through barrier requests.  Without disabling the
> volatile write cache on the disks you will lose data everytime the
> machine is not shut down cleanly.  The messages you see are typical
> for that kind of corruption.

The caches are all off.

| # hdparm -W /dev/hd[abeg]
| 
| /dev/hda:
|  write-caching =  0 (off)
| 
| /dev/hdb:
|  write-caching =  0 (off)
| 
| /dev/hde:
|  write-caching =  0 (off)
| 
| /dev/hdg:
|  write-caching =  0 (off)

I learned about this and deactivated the caches about half a year back, and
luckily didn't run into any problems before then. The machine has been rebooted
since then several times without any issues, so I don't think this could be a
left-over artifact from back then.

Thanks,

Philipp