Solid state drives

Simon Wilcox essuu at
Tue Apr 20 11:44:45 BST 2010

On 20/4/10 11:03, David Precious wrote:
> On Tuesday 20 April 2010 10:36:54 Simon Wilcox wrote:
>> On 20/4/10 10:07, James Laver wrote:
>>> On Tue, Apr 20, 2010 at 09:08:10AM +0100, Richard Huxton wrote:
>>>> Having said that, there are clearly plenty of applications where
>>>> power-failure isn't an overriding worry.
>>> Or 'on any machine connected to a UPS that's correctly configured to
>>> shut the machine down properly'?
>>> Or 'on any machine in a datacenter with generators for backup power'.
>> These are not the same. Ironically, in a datacentre with generators for
>> backup power, you are MORE likely to experience sudden power loss than
>> on a machine with a properly configured UPS.
>> The infrastructure of a commercial datacentre (e.g. Telehouse/HEX etc)
>> rarely has the means to send shutdown commands to servers if any
>> problems are experienced with the power feeds, meaning the UPSs will
>> inevitably run out of power whilst the engineers run around in circles
>> and you are unlikely to find out about it in time to do an orderly
>> manual shutdown.
> Or if a PSU goes bang and manages to trip out the supply to a rack...
> (Yeah, ideally you'd be running a dual-PSU box with each PSU connected to a 
> different supply, so you should never lose both, of course.)

Or the battery that enables the power switch over from generator to 
mains goes flat during an extended power outage resulting in an 
inability to switch from generator feed to mains power causing the 
building to fall over when the UPS runs out.

'Cos that's never happened. Grrrrrr.


More information about the mailing list