Re: Linux does not care for data integrity (was: Disk write cache)

[Matthias Andree <matthias.andree@gmx.de>]

On Mon, 16 May 2005, Arjan van de Ven wrote:

> I think you missed the part where disabling the writecache decreases the
> mtbf of your disk by like a factor 100 or so. At which point your
> dataloss opportunity INCREASES by doing this.

Nah, if that were a factor of 100, then it should have been in the OEM
manuals, no?

Besides that, although my small sample is not representative, I have
older drives still alive & kicking - an MTBF of 1/100 of what the vendor
stated would mean the chance of failure way above 90 % by now, the drive
has seen 22,000 POH with write cache off and has been a system drive for
like 14,000 POH. So?

> Sure you can waive rethorics around, but the fact is that linux is
> improving; there now is write barrier support for ext3 (and I assume
> reiserfs) for at least IDE and iirc selected scsi too. 

See the problem: "I assume", "IIRC selected...". There is no
list of corroborated facts which systems work and which don't. I have
made several attempts in compiling one, posting public calls for data
here, no response.

I don't blame you personally, but the lack of documentation about such
crucial facts or generally documentation in Linux environments in general.

-- 
Matthias Andree
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