[LAU] [OT]: Hybrid SSD disks

[mauser at smoors.de]

On 12.01.2012 10:31, Lorenzo Sutton wrote:
> Hi all,
>
> I've lately heard of so-called hybrid ssd disks and was wondering if
> anyone has experiences with them esp. relating to audio, but also for
> general use.
>
> While advantages (and drawbacks) of pure SSD are quite
> straightforward, but the price tag is still high, I'm not totally
> convinced of the advertised 'advantages' of the hybrid ones.
>
> On the more linux side of things, one aspect which is not very clear
> to me is compatibility, especially what sort of software hackery the
> 'adaptive' optimisations include and to which extent these are
> Windows/Mac only, e.g. one of the popular brands states Linux
> compatibility and in the spec. sheet "Can be used with Linux"

Hi Lorenzo,

those devices are completely transparent to the operating system. 
You're OS sees just one drive. The real magic is the algorithm inside 
the disc controller which decides which block should go on the SSD. This 
is implemented in the firmware of the device, it is not done via a 
driver. You can expect benchmarks around 110MB(MB/s) (r/w) from such a 
disk, which places the hybrid disc somewhere between the classic disc 
drives and older SSDs. This goes for the price as well..

When speaking about the use of those discs in audio systems you have to 
define the exact use case.. I don't think they make a lot of sense for 
the classic recording application, since the the caching algorihm places 
only popular blocks on the SSD. This will be useless if you're doing 
recordings all the day. It might be of use if you're using a sampler and 
playing the same samples a lot of times..
But you can only speculate about this case since no one knows the 
caching algorithm of the disc.

Hope that helps,
Sebastian