[Info-vax] Databases versus RMS

[Paul Sture]

On Fri, 20 Apr 2012 19:39:48 +0000, Phillip Helbig---undress to reply
wrote:

> In article <jmqv2n$9f5$1 at news.albasani.net>, Jan-Erik Soderholm
> <jan-erik.soderholm at telia.com> writes:
> 
>> The DECs SSD in SSB's (StorageWorks disks) was RAM based as far as I
>> know. That is, did not retain data at power loss. Was often used as one
>> part of a schadow-set so that all reads was doen from the RAM disks and
>> all writes went to both (and thus stored permanently).
> 
> I have a couple and they do retain their contents.  I assume they write
> the contents to disk when "spinning down" and/or when the power goes
> off.  EZ32: 268 MB.
> 
>> Modern SSD (Solid State Disks) are more or less always Flash-based and
>> thus retain data at a power loss. Many uses a Flash SSD as their only
>> disks in theirs laptop replacing the original rotating hard disk.
> 
> Right.  Also, the iPad has this as its "disks" (in addition to RAM). The
> flash disks are fine for some things but with lots of I/O they die
> pretty quickly (even after a few hours for really intensive I/O
> operations) while a conventional disk can last for years.

The MacBook Air has SSDs too.  Technology has advanced a lot in recent 
years and they no longer die so swiftly.  IBM have been using them for 
system disks, including pagefile disk for quite some time now.



-- 
Paul Sture