Re: [gentoo-user] {OT} SSD instead of RAID1?

[Grant <emailgrant@gmail.com>]

>> Anyway, the point of all this is to prevent an HD failure from
>> stopping the system.  An SSD is much safer, right?
>
> SSDs are still relatively new technology, so predicting failure rates is
> less reliable. What's wrong with using RAID-1? It's proven technology and
> totally resistant to a single HD failure.

Well, I've read great things about the reliability of SSDs.  Here's a
comment from Samsung:

http://www.engadget.com/2008/02/23/samsung-puts-the-kibosh-on-ssd-reliability-worries/

"a pattern could be perpetually repeated in which a 64GB SSD is
completely filled with data, erased, filled again, then erased again
every hour of every day for years, and the user still wouldn't reach
the theoretical write limit"

So in theory, the things are very reliable, but we wonder how they do
in the real world.

I'm considering a Super Talent Ultradrive which uses the relatively
new Indilinx controller.  There are 60 reviews of these drives on
newegg.com.  Of these 60, there are only 2 reports of operational
problems, most of the remainder are glowing tales of speed and
silence.  This is a "cheap" drive using technology that is new even
for an SSD, and still the newegg.com reports aren't dominated by
reports of "DOA!" or "Failed within 1 week!" like all of the
newegg.com HD reports I've seen.  Of course, this is far from
empirical evidence of SSD reliability, but it's very encouraging.

I shy away from RAID1 for a few reasons.  I posted these a little while ago:

1. RAID is another layer to learn, install, and maintain.

2. RAID isn't foolproof:

http://hardware.slashdot.org/article.pl?sid=08/10/21/2126252&from=rss
http://blogs.zdnet.com/storage/?p=162

3. RAID is relatively expensive on a hosted server.  Let's assume that
without RAID, the hard drive in use fails every 3 years and causes 24
hours of downtime with good backups.  That's a loss of .09% uptime
over 3 years.  If the server makes $100,000/year (and the same amount
every day), that's a loss of $273 over 3 years.  However, my host
wants $105/month for a second 15k hard drive and RAID controller card.
 The cost of that over 3 years is $3,780.

- Grant