Re: Block-level access

From: Alex Austin
Date: Thu Sep 01 2016 - 17:48:35 EST


CC'ing linux-scsi and linux-block.

Also, please CC me in replies.

On Thu, Sep 1, 2016 at 4:43 PM, Alex Austin <aaustin@xxxxxxxxxxxxxxxxxxx> wrote:
> Hello,
> What is the most performant way to directly interface with an attached hard
> drive? I've so far used read()/write() on /dev/sd_ but I find error handling
> exceedingly difficult, as I don't always even get errors reported, even if the
> open() call includes O_DIRECT. I've also used ioctl(SG_IO), but find that it's
> extremely slow due to the lack of queuing support in the API. Is there a
> mid-level API that will get me decent error handling while allowing command
> queuing, or do I just need to make multiple threads all doing separate SG_IO
> ioctls?
>
> Thank you,
> - Alex Austin
>
> --
> Intelligence is knowing that a tomato is a fruit; wisdom is knowing that it
> doesn't go in a fruit salad; charisma is selling a tomato-based fruit salad.



--
Intelligence is knowing that a tomoato is a fruit; wisdom is knowing
that it doesn't go in a fruit salad; charisma is selling a
tomato-based fruit salad.