SSHD ( Hybrid drive ) cache pinning

SSHD ( Hybrid drive ) cache pinning

[Phillip Susi]

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Hybrid hard drives are coming to market ( I will soon have one for
testing ) that use flash to cache the rotating media.  While the drive
firmware will attempt to figure out what blocks you frequently access
randomly ( not streaming IO ), and try to cache them in the flash,
ATA8 does add commands to allow the OS to explicitly control what
blocks are cached, and it should be in a better position to know what
should be there than the heuristics in the drive firmware.

Has there been any work done yet ( or even just design ) on
implementing this in linux?

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Re: SSHD ( Hybrid drive ) cache pinning

[Jeff Moyer]

Phillip Susi <psusi@ubuntu.com> writes:

> Hybrid hard drives are coming to market ( I will soon have one for
> testing ) that use flash to cache the rotating media.  While the drive
> firmware will attempt to figure out what blocks you frequently access
> randomly ( not streaming IO ), and try to cache them in the flash,
> ATA8 does add commands to allow the OS to explicitly control what
> blocks are cached, and it should be in a better position to know what
> should be there than the heuristics in the drive firmware.
>
> Has there been any work done yet ( or even just design ) on
> implementing this in linux?

Have a look at this thread:
  http://www.gossamer-threads.com/lists/linux/kernel/2037810

Cheers,
Jeff