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Subject: Re: IBM blade server abysmal disk write performances
From: Ian Lepore <ian@FreeBSD.org>
To: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
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On Fri, 2013-01-18 at 20:37 +0100, Wojciech Puchar wrote:
> >> disk would write data
> >>
> >
> > I suspect that I'm encountering situations right now at netflix where this advice is not true.  I have drives that are seeing intermittent errors, then being forced into reset after a timeout, and then coming back up with filesystem problems.  It's only a suspicion at this point, not a confirmed case.
> true. I just assumed that anywhere it matters one would use gmirror.
> As for myself - i always prefer to put different manufacturers drives for 
> gmirror or at least - not manufactured at similar time.
> 

That is good advice.  I bought six 1TB drives at the same time a few
years ago and received drives with consequtive serial numbers.  They
were all part of the same array, and they all failed ("click of death")
within a six hour timespan of each other.  Luckily I noticed the
clicking right away and was able to get all the data copied to another
array within a few hours, before they all died.

-- Ian

> 2 fails at the same moment is rather unlikely. Of course - everything is 
> possible so i do proper backups to remote sites. Remote means another 
> city.